debug print general activation through G_FireTarget
start to make use of entities debug print in other functions too, to get a generally similar look for ease of use, and possibly print more information in some places
make action names case-sensitive
remove unnecessary string copying

thanks to DevHC for pointing this out
fix G_FireRandomTargetOf's storing of choices

thanks to DevHC for noticing this
general code clean up

 * add const to parameters
 * remove spelling mistakes, redundant terms and whitespace problems in printouts
 * remove unnecessary checks
 * copy struct by assignment operator
 * make command description more consistent
 * avoid undefined qboolean enum assignment from bitmask checks with the help of doublenegations
 * use size_t instead of int in fieldoffsets
 * remove unnecessary initializations
 * rename some variables for clarity

thanks to DevHC for pointing out these things
Revert 1db8fcfc, since it was just a pointer after all

Revert "correct the gentity warning comment to include the fact, that the playerstate is expected as next element as well"

This reverts commit 1db8fcfc9f13cceebd1f6149eec6275a622b669d.