Separate UIKit-dependent code, make podspec OS X compatible
Add AppKit login controller, fix clear keychain method on OS X
Remove OS X specific clearing keychain code (unreliable)
Switch AppKit login controller to window controller subclass
Fix upload file headers
Add NSColor instanciation for annotations with AppKit
Merge branch 'MOB-817_MendeleyKit_MacOSX' of https://github.com/shazino/mendeleykit into shazino-MOB-817_MendeleyKit_MacOSX

Conflicts:
	MendeleyKit.podspec
Merge branch 'shazino-MOB-817_MendeleyKit_MacOSX' into MOB-817_MendeleyKit_MacOSX

* shazino-MOB-817_MendeleyKit_MacOSX:
  Add NSColor instanciation for annotations with AppKit
  Fix upload file headers
  Switch AppKit login controller to window controller subclass
  Remove OS X specific clearing keychain code (unreliable)
  Add AppKit login controller, fix clear keychain method on OS X
  Separate UIKit-dependent code, make podspec OS X compatible