remove build-and-run script for lmrmodelviewer
delete Ship::Animation and SpaceStation::Animation enums
add an allowPlaceholder parameter to Pi::FindModel (defaults to true)
fix the shipstat dumping code to work without LMR
update doc comment for ShipFlightState enum (no longer used by LMR)
update comments (strip all references to LMR)

It's like it never existed! Sort of.
Missing Accept visitor functions in some nodes
Merge remote-tracking branch 'luomu/fix-2074'
Merge remote-tracking branch 'johnbartholomew/remove-lmr-loose-ends'