In no particular order:
-----------------------

stubify C API.

replace EPS support with TK photo image support

Add command arguments for create, destroy, etc. so there would be a
-createcommand option to the togl command (etc.) (and phase out
Togl_*Func from the C API)

multisampling support (can be worked-around by passing in a pixelformat)

add vertical sync control

update documention
- update build instructions
- update stereo documentation
- separate Tcl API from C API
- say togl hides window system dependent (glX/wgl/agl) calls

