Remove XCode specific files.
Merged with develop, 3.7.0.
Update podspec file.
Update CHANGELOG
* update version.
Merge branch 'master' of github.com:pubnub/objective-c
* updated readme with additional message sending methods and APNS/GCM example
* fixed presence request timeout value
* adjusted code to remove warning if client added with CocoaPods
* fixed crypto heler initialization found by community
* tweaked logger code for client

[#81416874]
Merge branch 'hotfix-pt81416874' into develop