Save mines laid by player

[Kortonki]

Check whether there is a minefield close already

If not, create a new one

Use by the "put" eventhandler in the initUnitFIA and Initplayer

[Kortonki]

Works as intended but:

For some reason doesn't delete the original put mine when spawning the minefield Figure a way to assess proper sunk weight for the spawned mines

[Kortonki]

For original mine not deleted - consider waiting for the minefield to spawn, then use addtominefield for the laid mine. No dublicates and explosive ownership stays normal.

At the same time, consider ownership of loaded explosives to AS_commander

[Kortonki]

Needs to figure out to sink spawned mines still