This commit fixes the bug that the bgfx does not respect the `devicePixelRatio` parameter passed to nanovg's `nvgBeginFrame()` function. The problem is caused by the `bgfx::setViewRect()` call defined in the `nvgRenderViewport()` function, as it should take size in consideration of the `devicePixelRatio` value.
However, this commit does not fix nanovg's example app because currently there is no easy way to pass the scale value to the `ExampleNanoVG::update()` method as it calls `nvgBeginFrame()`.
On Android WillSuspend and WillResume maps to focus and DidSuspend and
DidResume maps to onPause and onResume.
On OSX WillSuspend and DidSuspend maps to resign key, WillResume and
DidResumg maps to make key.
added ios/osx bundle resource loading
added info.plist for iOS Xcode examples
Xcode now uses only Universal target ( should use 'Standard' as it is default in Xcode projects - this will require modification of genie)
