Merge pull request #127 from nlambson/master

Update Mantle dependency to latest 1.5 & fix related Model issues
Added canvas login and site admin login options
Merge remote-tracking branch 'instructure/CanvasKit/master'

Conflicts:
	CanvasKit/UIKit+CanvasKit/CKILoginViewController.m
Builds with iOS 7 SDK
Merge pull request #128 from derrh/master

Added canvas login and site admin login options
CanvasKit v0.52
Merge pull request #129 from derrh/master

CanvasKit v0.52
added swift unit testing. Finished unit test for CKIUser
Merge remote-tracking branch 'upstream/master'

Conflicts:
	Podfile.lock
Merge pull request #130 from elgreco84/master

Swift unit testing and updated to framework
added swift tests for following models:

CKIExternalTool
CKIDiscussionTopic
CKIActivityStreamMessageItem
CKIActivityStreamItem