Swapped source files for submodules
Added compiler flags, reference to prefix file
Changed framework path to modules dir, recursive
Moved ConnectSDK.h into core
Added default platforms constant
Fixed bad reference to ConnectSDK.h
Made ConnectSDK.h a public header
Update submodules for recent project file changes
Fixed typo in default platforms list
Updated readmes to include directions for modules
Merge remote-tracking branch 'origin/modularization' into sdk_1.4-dev
Merge remote-tracking branch 'origin/master' into sdk_1.4-dev

Conflicts:
	ConnectSDK.xcodeproj/project.pbxproj
	ConnectSDK/ConnectSDK-Prefix.pch
	ConnectSDK/Discovery/DiscoveryManager.m
	ConnectSDK/Services/CastService.m
	ConnectSDK/Services/Sessions/CastWebAppSession.h
	ConnectSDK/Services/Sessions/CastWebAppSession.m
Updated changelog
Merge remote-tracking branch 'origin/sdk_1.4-dev' into sdk_1.4
Updated repos
Added ImageInfo and MediaInfo classes
Update submodules
Updated podspec to require google-cast-sdk 2.4.0
Added DLNA event subscription support
Added support for Google Cast 2.4.0