NEW Feature: added SHKUploadsViewController
Merge branch 'master' into SHKUploadsViewController

* master:
  NEW FEATURE: Tap to dismiss on SHKActivityIndicator if upload progress is displayed. UploadProgressUserInfo enhanced too.
Merge branch 'master' into SHKUploadsViewController

* master:
  podspec 2.5.3 bump
  BUGFIX: even if useAppleShareUI was set to YES, ShareKit’s native form was sometimes presented.
NEW FEATURE: uploads view working live. Added SHKUploadInfo class, which encapsulates upload progress information.
BUGFIX: Fixed SHKActivityIndicator behaviour when dealing with multiple sharers at once. Only the latest sharer displays info on indicator, older ones continue to share silently.
NEW FEATURE: SHKActivityIndicator has circular progress view
NEW FEATURE: Dropbox & YouTube file share can be cancelled
FLICKR: can send mp4 videos
Merge branch 'master' into SHKUploadsViewController

* master:
  BUGFIX: google plus supplies different scheme if authorisation callback is from safari, or installed app. Fixes #859 and #860
LOCALIZATION: added activity indicator and uploads view tokens. Removed some duplicities