B9PartSwitch v1.1 for KSP 1.1

Changes

• KSP 1.1 compatibility
• Fixed bug where having part switching on the root part would cause physics to break
• Moved UI controls to UI_ChooseOption
• Adjust default Monopropellant tank type to be closer to (new) stock values
• Use stock part mass modification
• Hopefully fix incompatible module checking
• Various refactors and simplifications which might improve performance a bit

Known Issues

• Still no TweakScale compatibility