Fix broken links in contributor-doc

contributor_docs/creating_libraries.md

@@ -303,7 +303,7 @@ p5.prototype.myMethod = function(){
 
 **Contributed libraries are hosted, documented, and maintained by their creators.** This could be on GitHub, a separate website, or elsewhere. We only feature addon libraries that are fully open source.
 
-**Documentation is key!** The documentation for your library should be easy to find. The documentation for contributed libraries won’t be included in the main p5.js reference, but you may want to follow a similar format. See these examples of a [library overview page](http://p5js.org/reference/#/libraries/p5.sound), [class overview page](http://p5js.org/reference/#/p5.Vector), and [method page](http://p5js.org/reference/#/p5/arc).
+**Documentation is key!** The documentation for your library should be easy to find. The documentation for contributed libraries won’t be included in the main p5.js reference, but you may want to follow a similar format. See these examples of a [library overview page](https://p5js.org/reference/p5.sound), [class overview page](https://p5js.org/reference/p5/p5.Vector), and [method page](https://p5js.org/reference/p5/arc).
 
 **Examples are great, too!** They show people what your library can do. Because this is all JavaScript, people can see them running online before they download anything.[ ](http://jsfiddle.net/) You can create a collection of examples on the p5.js web editor to showcase how your library works.
 

contributor_docs/how-to-add-friendly-error-messages.md

@@ -189,7 +189,7 @@ In the example above, anything in double angle brackets (`{{}}`) is something th
 
 After adding your case, you can now call `p5._friendlyFileLoadError([case number], [file path])` inside your error handling statements.
 
-For example, please take a look at `loadStrings()` method loading a string-based file (which corresponds to `case 3` from `fileLoadErrorCases`). The  `loadStrings()` method uses [`httpDo.call()`](https://p5js.org/reference/#/p5/httpDo) with a custom callback method that is executed in the case of a file error:
+For example, please take a look at `loadStrings()` method loading a string-based file (which corresponds to `case 3` from `fileLoadErrorCases`). The  `loadStrings()` method uses [`httpDo.call()`](https://p5js.org/reference/p5/httpDo) with a custom callback method that is executed in the case of a file error:
 
 ```js
 p5.prototype.httpDo.call(