Add serialization support for std::unordered_map and std::unordered_set
Serialize KeyboardTogglesGraphicsBehavior, add UnitTest
Fix header character case and use 'typedef' to fix Linux build failure
Change signature of 'getKeyboardRegister()', let it return a 'const &'.
Update UnitTest, comments, and documentation.
Change 'register' to 'registry'
Fix UnitTest failure
add textured and shadowed material
Add the ability to assign a minimal texture unit to OsgTextureUniform, this lets us manage the range of texture units for binding and interactions with shaders
Resolve name conflict between DataStructuresConvert and MathConvert

'serializeLogger' is conflicting. Change 'serializeLogger' in
DataStructureConvert to'loggerName'.

Also, update other variables' name based on naming convention.
Use concrete objects in KeyboardTogglesGraphicsBehavior's UnitTest
Initialize the graphics meshes with correct scale.
Fix RenderTest

add default textures
fix documentation
Put YAML ID strings in specialized namespaces to avoid symbol conflict.
OsgCamera unit tests.
Serialize OsgView and add unit tests.

- Test all serialized members of OsgView.
- Change the serialized type of ScreenWidth/ScreenHeight to double.
Add setDrawAsWireFrame to all OsgRepresentations

Move the setDrawAsWireFrame up from the OsgMeshRepresentation to all
OsgRepresentations. The code is the same, and now all representations
can be rendered as wire frames.
Fix builds with gcc-4.9

Somewhere in the old ply code, macros are being misused. With gcc-4.9,
this misuse causes an error in our code the first time cstddef is
included after ply.h. So, we just need to include cstddef at the
beginning of ply.h. See the explaination and suggested solution here:

  https://gcc.gnu.org/gcc-4.9/porting_to.html
Merge branch 'master' into feature/textured-material
Fix Typo