Improvements to access for Optional Value
Improve Stapling demo.

- Remove resetting rigid representation to initial state when it goes to
  inactive.
- Increase the size of the virtual teeth of the stapler.
Static casts to prevent conversion warnings on 64 bit builds, in devices
Find the 64bit drivers for the LabJack on Windows in 64bit builds.

64 bit builds already work on Linux.
Make OsgOctreeRepresentation serializable

OsgOctreeRepresentation previously accepts an OctreeShape and
retrieve the Octree stored in the OctreeShape and visualize it.
However, this is not serializable since the OctreeShape is not stored.

After this change, OsgOctreeRepresentation will store a shared reference
to the OctreeShape. This OctreeShape will be serialized and deserialized
during serialization.
Corrected static_cast of number of timers in LabJackScaffold.

The function's argument is for a double, even though the number of
timers must be an integer.
Merge branch 'fix/64bit-devices' into 'master'

Fix build errors for LabJack and Novint in 64bit

Merged-on: https://www.assembla.com/code/OpenSurgSim/git/merge_requests/1029934
Fix Documentation
Remove unused variable
Add serialization UnitTest for OsgOctreeRep, remove unused headers.
Merge remote-tracking branch 'origin/master' into feature/OsgOctreeRepresentatin-Serialization
Merge branch 'feature/optional-value-dereference' into 'master'

Better access to OptionalValue values

Merged-on: https://www.assembla.com/code/OpenSurgSim/git/merge_requests/1026444
Merge branch 'fix/stapling-demo-improvement' into 'master'

Stapling demo: Remove reset state for staple goes inactive + Larger virtual teeth

+1: Julien Lenoir, Harald Scheirich, haizhouW

Merged-on: https://www.assembla.com/code/OpenSurgSim/git/merge_requests/1029104
Merge remote-tracking branch 'origin/master' into feature/OsgOctreeRepresentatin-Serialization
Merge branch 'feature/OsgOctreeRepresentatin-Serialization' into 'master'

Serialize OsgOctreeRepresentation

Merged-on: https://www.assembla.com/code/OpenSurgSim/git/merge_requests/1032574