Added the Mech Ion Rifle, Mech Carbine, Mech Rocket Launcher
and Ion Rifle to the list of things you can build with the
Protolathe and Exosuit Fabricator.
Added costs for the Mech Ion Rifle and the Mech Rocket Launcher.
Merge pull request #2341 from ManeaterMildred/MechDesign

Mech Weapons researching.