Adds visual tests for Isometric mapping

Changes the name of math constants to be consistent

 Adds fade background with typical paraview style bg colors.
TODO : make this a renderer setting and optional

Changes names of math constants

Uses imstk defined math constants

Adds geometry map base class and isometriMap

Signed-off-by: Sreekanth Arikatla <sreekanth.arikatla@kitware.com>

- Remove PThreads on Linux
- Correct CMake output directories in case of single
configuration type (not MSVC)

Corrects bug on Windows

Default is OFF since we have issues configuring
it on Windows currently.

All projects output directories are now common in
the top level. This commit takes care of the
CMAKE_CONFIGURATION_TYPES for Visual Studio.

With this commit the Find_XXX.cmake files do not need
HINTS anymore since all targets are built in a same
directory known to CMAKE_LIBRARY_PATH, and all headers
directories are referenced in CMAKE_INCLUDE_PATH.

The scene needs to be paused, but not the viewer.

Also make Geometry class polymorphic by making its
destructor virtual.

Conflict existed within VTK.

Can directly used to create visual objects.

Also use unordered_map in SimulationManager.

This base class was needed for storing position and
orientation of the geometries. Those global transformation
can also be applied to discrete geometries, therefore
Geometry and AnalyticalGeometry classes were merged.

Was not applying the quaternion on the good side.

Core sprint

Include Core sprint branch into refactoring branch.

- CMake architecture / Superbuild
- Uncrustify for code style checking
- G3log for logging
- Core classes : SimulationManager, Module, & Scene

See merge request !79

Had to pass g3log_SOURCE_DIR from the superbuild to
the inner build to be able to find the librairies for
g3log in Findg3log.cmake.