Reverted both LordBraindead and my own work on firecode back to when it was stable.  Fixed some issue with phantom-fires-in-pipes.  Removed some useless things left over from FEA.
Merge pull request #3726 from SkyMarshal/firefixes

Reverted both LordBraindead and my own work on firecode back to when it was stable.
Garbage collection for fire and explosive particles.

Signed-off-by: Mloc-Argent <colmohici@gmail.com>
Merge pull request #3730 from Mloc/gc-

Garbage collection for fire and explosive particles.
Merge pull request #3734 from Baystation12/master

Master -> dev