Fix unit selection hotkeys for players. Fixes #5753.

This also explicitly disables them for spectators.
Fixed 'seven-stairs' and 'room-warzone'
Added the abiltity to load WVec[] from MiniYaml
send player names to master server
Applied VWec[] yaml loader
Merge pull request #6111 from abcdefg30/fixmaptiles

Fixed 'seven-stairs' and 'room-warzone'
Add ITraitInfo constraint to Requires<T>
Merge pull request #6102 from ihptru/masterplayers

send player names to master server
Merge pull request #6121 from ScottNZ/bleed

Add ITraitInfo constraint to Requires<T>
Merge pull request #6113 from atlimit8/FieldLoadWVecArray

Load WVec[] from MiniYaml
Merge pull request #6098 from pchote/select-hotkey

Fix unit selection hotkeys for players.
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.
Remove redundant UpgradeTypes property.