fix: remove empty authors (dash is alone)

Used regex: `-\s+(\(|$)`

books/free-programming-books-id.md

@@ -136,7 +136,7 @@
 ### PHP
 
 * [Belajar Laravel Untuk Pemula](https://gilacoding.com/upload/file/Belajar%20Laravel%20Untuk%20Pemula.pdf) - Dadan Hamdani (PDF)
-* [Membuat Bot Telegram dengan PHP](https://www.slideshare.net/HasanudinHS/ebook-i-membuat-bot-telegram-dengan-php) - Hasanudin H Syafaat - (PDF)
+* [Membuat Bot Telegram dengan PHP](https://www.slideshare.net/HasanudinHS/ebook-i-membuat-bot-telegram-dengan-php) - Hasanudin H Syafaat (PDF)
 * [Menjelajahi Yii Framework](https://gilacoding.com/upload/file/menjelajahyiiframework.pdf) - Sabit Huraira (PDF)
 * [Pemrograman Berbasis Objek Modern dengan PHP](https://arsiteknologi.com/wp-content/uploads/Pemrograman_Berbasis_Objek_Modern_dengan_PHP_Google_Play_Book.pdf) - Muhamad Surya Iksanudin (PDF)
 * [Pemrograman Berorientasi Objek Dengan PHP5](https://endangcahyapermana.files.wordpress.com/2016/03/belajar-singkat-pemrograman-berorientasi-objek-dengan-php5.pdf) - Gerry Sabar (PDF)
@@ -152,7 +152,7 @@
 * [Belajar Python](http://www.belajarpython.com)
 * [Dasar Pemrograman Python](https://www.pythonindo.com/tutorial-python-dasar/)
 * [Dasar Pengenalan Pemrograman Python](https://play.google.com/store/books/details/Rolly_Maulana_Awangga_Dasar_dasar_Python?id=YpzDDwAAQBAJ) - Rolly Maulana AwanggaRayhan *(Membutuhkan akun Google Play Books atau email yang valid)*
-* [Database PostgreSQL, Pemrograman Python, dan SMS Gateway](http://rab.co.id/files/python/bukupython2.pdf.gz) - (PDF)
+* [Database PostgreSQL, Pemrograman Python, dan SMS Gateway](http://rab.co.id/files/python/bukupython2.pdf.gz) (PDF)
 * [Kursus Singkat Machine Learning dengan TensorFlow API](https://developers.google.com/machine-learning/crash-course?hl=id)
 * [Tutorial Python](https://docs.python.org/id/3.8/tutorial/)
 * [Workshop Python 101](http://sakti.github.io/python101/)

books/free-programming-books-it.md

@@ -99,7 +99,7 @@
 ### C
 
 * [Guida di Beej alla Programmazione di Rete - Usando Socket Internet](http://linguaggioc.altervista.org/dl/GuidaDiBeejAllaProgrammazioneDiRete.pdf) - Brian "Beej Jorgensen" Hall, Fabrizio Pani (PDF)
-* [Il linguaggio C - Guida pratica alla programmazione](https://eineki.files.wordpress.com/2010/02/guidac.pdf) - (PDF)
+* [Il linguaggio C - Guida pratica alla programmazione](https://eineki.files.wordpress.com/2010/02/guidac.pdf) - BlackLight (PDF)
 * [Linguaggio C - ANSI C](https://web.archive.org/web/20180920221053/http://www.itis.pr.it/~dsacco/itis/Olimpiadi-informatica/Libri-di-testo/LinguaggioC-R&K.pdf) - Brian W. Kernighan, Dennis M. Ritchie (PDF) *(:card_file_box: archived)*
 * [Linguaggio C - Guida alla programmazione (1999)](http://www.cbmc.it/~marchettil/Tandem2016/Bellini.pdf) - A. Bellini, A. Guidi (PDF)
 * [Tricky C](http://www.dmi.unict.it/diraimondo/web/wp-content/uploads/classes/so/mirror-stuff/Tricky_C.pdf) (PDF)
@@ -112,8 +112,8 @@
 
 ### <a id="cpp"></a>C++
 
-* [Corso C++ standard](http://didatticait.altervista.org/programmazione/CPP/CPP-dispense/CORSO_C.pdf) - (PDF)
-* [Il linguaggio C++](https://hpc-forge.cineca.it/files/CoursesDev/public/2012%20Autumn/Introduzione%20alla%20programmazioni%20a%20oggetti%20in%20C++/corsocpp.pdf) - (PDF)
+* [Corso C++ standard](http://didatticait.altervista.org/programmazione/CPP/CPP-dispense/CORSO_C.pdf) (PDF)
+* [Il linguaggio C++](https://hpc-forge.cineca.it/files/CoursesDev/public/2012%20Autumn/Introduzione%20alla%20programmazioni%20a%20oggetti%20in%20C++/corsocpp.pdf) (PDF)
 
 
 ### Database

books/free-programming-books-langs.md

@@ -503,7 +503,7 @@ That section got so big, we decided to split it into its own file, the [BY SUBJE
 * [C++ Succinctly, Syncfusion](https://www.syncfusion.com/resources/techportal/ebooks/cplusplus) (PDF, Kindle) (email address *requested*, not required)
 * [C++ Tricks](http://www.bordoon.com/cplusplus/book_wrapper.html)
 * [CS106X Programming Abstractions in C++](http://web.stanford.edu/class/cs106x/)
-* [Elements of Programming](http://elementsofprogramming.com) - Alexander Stepanov, Paul McJones - (PDF)
+* [Elements of Programming](http://elementsofprogramming.com) - Alexander Stepanov, Paul McJones (PDF)
 * [Financial Numerical Recipes in C++](https://ba-odegaard.no/gcc_prog/recipes/) - Bernt Arne Ødegaard (PDF)
 * [Fundamentals of C++ Programming](https://web.archive.org/web/20191005170118/https://python.cs.southern.edu/cppbook/progcpp.pdf) - Richard L. Halterman (PDF) *(:card_file_box: archived)*
 * [Game Programming Patterns](http://gameprogrammingpatterns.com)
@@ -2064,7 +2064,7 @@ That section got so big, we decided to split it into its own file, the [BY SUBJE
 ### Raspberry Pi
 
 * [Raspberry Pi: Measure, Record, Explore](https://leanpub.com/RPiMRE/read) - Malcolm Maclean (HTML)
-* [Raspberry Pi Users Guide - (2012)](http://www.cs.unca.edu/~bruce/Fall14/360/RPiUsersGuide.pdf) - Eben Upton (PDF)
+* [Raspberry Pi Users Guide (2012)](http://www.cs.unca.edu/~bruce/Fall14/360/RPiUsersGuide.pdf) - Eben Upton (PDF)
 * [The Official Raspberry Pi Project Book 1 (2015)](https://magpi.raspberrypi.com/books/projects-1) (PDF)
 
 

books/free-programming-books-zh.md

@@ -662,26 +662,26 @@
 ### Python
 
 * [简明 Python 教程](https://web.archive.org/web/20200822010330/https://bop.mol.uno/) - Swaroop C H、沈洁元(翻译)、漠伦(翻译) *(:card_file_box: archived)*
-* [人生苦短，我用python](https://www.cnblogs.com/derek1184405959/p/8579428.html) - (内含丰富的笔记以及各类教程)
+* [人生苦短，我用python](https://www.cnblogs.com/derek1184405959/p/8579428.html) - zhang_derek *(内含丰富的笔记以及各类教程)*
 * [深入 Python 3](https://github.com/jiechic/diveintopython3)
-* [Matplotlib 3.0.3 中文文档](http://www.osgeo.cn/matplotlib/) - (Online)
-* [Numpy 1.16 中文文档](http://www.osgeo.cn/numpy/) - (Online)
+* [Matplotlib 3.0.3 中文文档](http://www.osgeo.cn/matplotlib/) (Online)
+* [Numpy 1.16 中文文档](http://www.osgeo.cn/numpy/) (Online)
 * [Python 3 文档(简体中文) 3.2.2 documentation](http://docspy3zh.readthedocs.org/en/latest/)
-* [Python 3.8.0a3中文文档](http://www.osgeo.cn/cpython/) - (目前在线最全的中文文档了，Online)
+* [Python 3.8.0a3中文文档](http://www.osgeo.cn/cpython/) (Online) *(目前在线最全的中文文档了)*
 * [Python 中文学习大本营](http://www.pythondoc.com)
 * [Python 最佳实践指南](https://pythonguidecn.readthedocs.io/zh/latest/)
 * [Python Cookbook第三版](http://python3-cookbook.readthedocs.io/zh_CN/latest/) - David Beazley、Brian K.Jones、熊能(翻译)
 * [Python教程 - 廖雪峰的官方网站](http://www.liaoxuefeng.com/wiki/0014316089557264a6b348958f449949df42a6d3a2e542c000)
 * [Python进阶](https://interpy.eastlakeside.com) - eastlakeside
 * [Python之旅](https://web.archive.org/web/20191217091745/http://funhacks.net/explore-python/) - Ethan *(:card_file_box: archived)*
-* [Tornado 6.1 中文文档](http://www.osgeo.cn/tornado/) - (网络上其他的都是较旧版本的，Online)
+* [Tornado 6.1 中文文档](http://www.osgeo.cn/tornado/) (Online) *(网络上其他的都是较旧版本的)*
 
 
 #### Django
 
 * [Django 1.11.6 中文文档](https://www.yiyibooks.cn/xx/Django_1.11.6/index.html)
-* [Django 2.2.1 中文文档](http://www.osgeo.cn/django/) - (这个很新，也很全，Online)
-* [Django 搭建个人博客教程 (2.1)](https://www.dusaiphoto.com/article/detail/2) - (杜赛) (HTML)
+* [Django 2.2.1 中文文档](http://www.osgeo.cn/django/) (Online) *(这个很新，也很全)*
+* [Django 搭建个人博客教程 (2.1)](https://www.dusaiphoto.com/article/detail/2) - 杜赛 (HTML)
 * [Django book 2.0](http://djangobook.py3k.cn/2.0/)
 * [Django Girls 教程 (1.11)](https://tutorial.djangogirls.org/zh/) (HTML)