Boarding

**What needs to be done?**

We need to implement boarding.

Basic mechanic: ship is adjacent to enemy ship in combat and enemy ship's shields are down; ship gains the ability to board enemy ship. This takes all the components with Boarding Attack ability and pits them against the enemy Boarding Defense and Crew Quarters components. All the attack components are destroyed and require repair. If boarding is successful (attack > defense), attacker gains control of enemy ship. Captured ship's weapons are temporarily disabled (how long?). If successful, all boarding defense components (but not crew quarters unless they have boarding defense ability) are destroyed. If boarding attempt fails, some of the boarding defense components are destroyed, proportional to boarding attack (I think). If boarding attempt succeeds AND target has a self destruct device, both ships are destroyed. Or do ships just refuse to board ships that have SDD's?

Potential enhancements:

* Allow vehicle types other than ships and bases to board.
* Add a boarding damage type - not so OP as the psychic mind screw!
* Allow planets to board? That would be insane...
* Allow vehicle types other than ships and bases to be boarded.
* Require target ship to be immobile or at least slower than boarding ship in order to board. (game/mod option?)
* Make boarding more complex, similar to ground combat - needs some thought!
* Allow boarding parties to go on other missions besides ship capture - say, sabotage, stealing supplies, assassinating officers (reducing experience)...
* Give self destruct ability a chance to succeed/fail when boarded rather than always succeeding.
* Toggle in ship strategy (once we have those) to board enemy ships with SDD's