Modify IS_WIDESCREEN to not use DBL_EPSILON

Could not reproduce DBL_EPSILON not found compiler error
locally (only on Travis CI).
Other fixes attempted:
  - Use include for float.h
  - Properly wrap all code in ifndefs
  - Update arch settings in xcode proj
  - Attempt to force travis to run iossimulator7.0/sdk7.0 and
    arch x64_86

Also updated Podfile, looks like MR was split into a core lib
  and some bonus dependencies. Run 'pod install' to update.