Makes LineBuild logic require building dimensions of 1x1
Added flag to Mobile/AircraftInfo: MoveIntoShroud.
Does not change the audio feedback given.
Fix instant-use and AllowMultiple support powers.

Fixes #2185, #6090.
Remove Infiltratable trait and refactor surrounding code to use target types
Rename IAcceptInfiltrator to INotifyInfiltrated
Merge pull request #6022 from Phrohdoh/MoveToShroud

Locomotion MovesToShroud bool.
Merge pull request #6135 from pchote/support-fix

Fix instant-use and AllowMultiple support powers.
Merge pull request #6069 from atlimit8/LineBuild-1x1Only

Makes LineBuild logic require building dimensions of 1x1
Merge pull request #6136 from ScottNZ/infiltration

Infiltration refactor
Move Power out of Building and into its own trait

Conflicts:
	mods/ts/rules/structures.yaml
Merge pull request #6133 from ScottNZ/power

Move Power out of Building and into its own trait
Support production of actors without IFacing.
Introduce IUpgradable and purchasable unit upgrades.
Reimplement UnitUpgradeCrate using IUpgradable.
Reimplement unit levels using IUpgradable.
Add FriendlyFire property to GivesExperience.
Replace CloakCrateAction with upgrades.