Flop and Roll added

-Fixed height sensors
-Added secondary (plane+box) ground for height sensors
-Added flop and roll  method to applyActions

-Still missing learning for flop and roll.
Includes crater class for compilation
Includes additional crater model
Adding Crater class to escape from
Minor edits, including prevention of some illegal final positions of model
Formatting
Merge branch 'master' of github.com:NASA-Tensegrity-Robotics-Toolkit/NTRTsim into crater
Added surrounding crater for tensegrity to escape out of
Commenting
Minor tweaks
Commented out assertion temporarily
Minor tweaks
Fixed the reset seg fault problem

On teardown, cleared the vector of objects that should be destroyed
with the reset
Tweaked parameters
Merge branch 'master' into crater
Cleaned up comments, minor reformats
Fixed typo
Cleaned comments, minor formatting
Tweaked parameters
Added CraterDeep compilation