Instead of limitating the number of bullets, according to the ones in screen, do...

Instead of limitating the number of bullets, according to the ones in screen, do it in a time bases.
This was asked in a comment on The Linux Game Tome and I already wanted to do this, since the day I made that hack, so here it goes.
You can tune that time on the defines.h file, it is the BULLETS_TIMEOUT definition (in ms). There is a fire test level.

SVN-Revision: 1059