3.0.1

EasyAR SDK 3.0.1 includes some bug fixes and user experience improvements.

Detailed changes are as bellow,

* add support of YUY2 and I420 pixel formats for cameras on Windows to reduce the possibility of black screen
* fix the crash at glDrawArrays in Objective-C samples, which is caused by dependent states of multiple instances of Renderer
* add support for png of 16-bit per channel
* fix texture coordinate problem with non-OpenGLES or screen rotation in Unity HelloAR_Coloring3D sample
* fix autofocus problem with Unity samples
* fix Unity samples for the problem that models are visible on startup and only disappear after a while
* remove initialization success banner from Unity samples
* add support for a secondary camera in Unity samples (ex. on Windows/Mac, a USB camera in addition to the built-in camera)
* rename ExternalCamera to CustomCamera to reduce ambiguity