Ported monster tank madness to lua

~~It would be nice, if someone could already have a look at this (style nits?),
although this is not completely finished yet (see todo).~~ See below.

[This](https://github.com/abcdefg30/OpenRA/commit/f5053eb1fba517de32725c6d9168480c4fc32c6f#diff-da0b70bbc22b6b4af2fbe96dd5c5a8b7R19) set to true can help testing.
As the super tanks will self destruct in 3 minutes, not 4.
Maybe I "in approximately" or "in about" would be better?
Or should I just say "in 3 minutes"?