What changed in EDuke32, build by build

fix m32script crash

add an EVENT_INIT that fires once per explicit `include` of a script filename from the console (including from within m32_autoexec.cfg)

add xfliphighlightedsectors/yfliphighlightedsectors/xmirrorhighlightedsectors/ymirrorhighlightedsectors to m32script, remove read-only flag from startpos vars so the map start position can be changed from scripts

clamp m32script line drawing color range to 255 instead of 15

handle negative color indexes for m32script printext16 the same as the line drawing commands