Beam targeting of CRPL cores broken in 1.72

[eduran]

As soon as a beam starts to shoot at a CRPL core the game does one of its semi-freezes. Simple test map to showcase the issue is attached, but it seems to happen on any beam targetable core.

[knucracker]

Yep, I inconveniently added a null pointer exception in 1.72 whenever a crpl tower takes damage.  It has to do with the red flash stuff I added in 1.72 when units take damage....  Will be fixed and a build up within the hour.