Technical junk commanders cause luarules errors

[GoogleFrog]

A bunch of stuff crashes because a spawned clonedef commander (dyncommbla5_1001 etc) has the custom params of a commander, but lacks the unit rules params it would get from being created by the dynamic commander gadget. They don't even know which weapons they are supposed to be able to fire.

Someone made a bug report with such a commander, so they should be removed from the technical junk menu. Their creation could also be disallowed via AllowUnitCreation in the dynamic commander gadget.

[sprunk]

If disallowing them via AllowUnitCreation don't forget to let rez and zombies through. Perhaps the dynamic comm gadget needs to handle those cases anyway due to #5140.