[FIXED][1405] Multimission tomahawks causes slowdown

[Swant]

Multimission tomahawks fired at a ship causes slowdown. When they are shot down the game runs normal.
Tomahawks fired at stationary land target doesn't seem to be an issue

[Dimitris]

Attempted to reproduce this in the current private dev build, but it runs very well. Probably fixed for next release as part of general speed tweaks from other (TERRIBLY demanding) stress tests.