MRProgress target settings in MRProgress.xcodeproj differs from target in Pod.xcodeproj

[jamieomatthews]

The project settings are different for the MRProgress target inside the main project from the settings in the Pod project. These should be the same. There are build errors in the main project that are being ignored by the pod project.

To be specific - the target in MRProgress.xcodeproj has some extra settings:

• Treat Warnings as errors - YES
• Other Warning Flags - "-Weverything -Wno-objc-missing-property-synthesis -Wno-auto-import -Wno-direct-ivar-access -Wno-gnu -Wno-cstring-format-directive"

This PR fixes the errors being warned about. Once this PR is merged, these settings should be applied to the pod target as well.

#123