Warnings fixed

Updated project file
Updated Classes to not use iOS 8 standart property description ->
objectDescription
Update to KinveyKit 1.27.1
Updated FB SDK to 3.20
Something strange with SDK on git =/
Update UI for iOS 7/8
Issue, when not able to work when do logout
Crash when tap on map annotation
Fixed Image preview, never appear nav bar
Update readme
fixed warnings, updated KinveyKit and Facebook SDK, updated UI for iOS 7/8, fixed image preview, closes #1