OpenGL-ES: Basic bringup of MOGL low-level OpenGL 3D rendering.

Add new helper functions IsGLES() and IsGLES1() to detect at runtime
if OpenGL-ES / OpenGL-ES1.x is in use as renderer, so code can adapt.

Implement alternative implementations of functions not supported on
GLES, by implementing them in the M-File mogl wrappers:

gluLookAt(), gluPerspective(), gluOrtho2D(), glOrtho(), glOrthof(),
glFrustum().

Make moglmorpher() mostly compatible with ES. Rendering to display
lists and retrieval of screen space vertex positions is not supported,
as the underlying gl functionality does not exist in ES. Normal rendering
was converted from immediate mode to vertex arrays batch rendering.
GPU based morphing is not yet supported, as it would require at least
OpenGL-ES2.x with additional floating point texture extensions.

Convert MorphDemo to make it OpenGL-ES compatible. Relatively minor
tweaks, as that demo mostly uses moglmorpher() for rendering, and
moglmorpher() mostly uses non-immediate mode rendering, so already
avoids the totally unsupported stuff. However, moglmorpher() can only
do cpu based morphing atm. due to lack of shader support in ES-1.

Having MorphDemo mostly work is an encouraging start!