Update README URLs based on HTTP redirects

[ReadmeCritic]

Created with https://github.com/dkhamsing/frankenstein

GitHub Corrected URLs

Was	Now
https://github.com/BoltsFramework/Bolts-iOS/releases	https://github.com/BoltsFramework/Bolts-ObjC/releases

HTTPS Corrected URLs

Was	Now
http://img.shields.io/cocoapods/l/Bolts.svg?style=flat	https://img.shields.io/cocoapods/l/Bolts.svg?style=flat
http://img.shields.io/cocoapods/p/Bolts.svg?style=flat	https://img.shields.io/cocoapods/p/Bolts.svg?style=flat
http://img.shields.io/cocoapods/v/Bolts.svg?style=flat	https://img.shields.io/cocoapods/v/Bolts.svg?style=flat
http://img.shields.io/travis/BoltsFramework/Bolts-iOS/master.svg?style=flat	https://img.shields.io/travis/BoltsFramework/Bolts-iOS/master.svg?style=flat

Other Corrected URLs

Was	Now
http://cocoapods.org	https://cocoapods.org/
http://www.applinks.org	http://applinks.org/
http://www.applinks.org/documentation	http://applinks.org/documentation/

[richardjrossiii]

LGTM. Passing to @nlutsenko for his feedback.

[nlutsenko]

Part of this is already part of #224, will update with changes from this. Thanks!

[facebook-github-bot]

@ReadmeCritic updated the pull request.