Refine Mesh interface

Derived a CubeMesh from Mesh, refine Mesh interface, manually creat
a Node in Scene Graph

Signed-off-by: Wayne Wolf <wayne.ron.wu@googlemail>
simply NativeCore virtual interface

Signed-off-by: Wayne Wolf <wayne.ron.wu@googlemail>
Node use auto program by default, save a call for user app

Signed-off-by: Wayne Wolf <wayne.ron.wu@googlemail>
change program uniform and attribute location store time

Signed-off-by: Wayne Wolf <wayne.ron.wu@googlemail>