Support older Adobe Texture Format version 2
Support older Adobe Texture Format version 2

There are 3 different versions of the ATF format. Only version 3 supports the ETC2 format.

NenadBojkovski/openfl,Gama11/openfl,Gama11/openfl,Gama11/openfl,Gama11/openfl,openfl/openfl,openfl/openfl,NenadBojkovski/openfl,openfl/openfl