The code is quite complex but I haven't found any easier way to do it 
(passing NULL as NUMBERFMT results in two decimal places being appended).

 - Added idl displaying.
 - Fixed AddToTLDataStrWithTabsW function.

- Use a list to keep track of what constants are set.
- Move TRACEs and checkGLcall calls out of the main constant loading loop.

Indices for the float constant map should be multiplied by 4 because
we're loading 4 component float vectors, not because the size of a
float is 4.