GEP does useless caching

[erkyrath]

Glulx Entry Points has a function GEP_TestGestalts which checks all the Glk and Glulx gestalt selectors and caches their results.

This appears to be done correctly -- that is, it's re-checked during IdentifyGlkObject(), which is important. However, it's kind of useless. The @gestalt opcode test is faster than an Inform array lookup. A glk_gestalt() call is slower by one function call but this is really not worth worrying about. (And even if it were, the time saved will usually be outweighed by the cost of caching the 35 values that most games ignore.)

Removing the function and the GEP_GlulxGestaltResults/GEP_GlkGestaltResults arrays would save some bytes and simplify the extension.

I think I've mentioned this before, so I apologize for being tedious about it.