Merge pull request alexeyxo#57 from sofacoder/bugfix/mergeFromFiled-c…

…reates-immutable-copies-for-mutable-types

[FIX] changed "copy" to "mutableCopy" for NSMutableArray types

Upgrade to Cocoapod 0.36.0.beta.1 requires Umbrella Header Usage alex…

…eyxo#28

Don't insert #import "ObjectivecDescriptor.pb.h" into generated code? a…

…lexeyxo#26

Update podspec alexeyxo#19

protocol buffers 2.6 cocoa pods