Don't utilize glPixelStorei's PACK/UNPACK IMAGE_HEIGHT and SKIP_IMAGES for Desktop GL < 1.2, avoiding GL-Error

Commit fc1e98790a02b4fa7922f3cdd9d437f87d7c99e5
added handling of PACK/UNPACK IMAGE_HEIGHT and SKIP_IMAGES in GLPixelStorageModes.

However, it has been overseen that the four states are not available in OpenGL 1.1.

Adding exclusion of the same if desktop GL < 1.2
and hence avoiding GL errors.

Same applies to GLBuffers.sizeof(..) method.
GLPixelStorageModes: Emphasize reset*() usage; setUnpackRowLength: GL2ES2 -> GL2ES3; Better adoption of GLPixelStorageModes (GLJPanel, GLReadBufferUtil, TextureIO)

- Emphasize reset*() is being called when saving modes for 1st modification;

- setUnpackRowLength: GL2ES2 -> GL2ES3; Actually GL2ES3 is required for UNPACK_ROW_LENGTH

- Better adoption of GLPixelStorageModes (GLJPanel, GLReadBufferUtil, TextureIO)
TestVersionSemanticsNOUI: v2.3.0 is not backward compatible w/ 2.2.*