Add collision Mesh to sphere and plane coll. detection classes based on brute force approach.

1) Change the interactionPair structure to save
only one collisiondata per structure, and inform
the collisionhandling of a "side" defining which
object it is handling, therefore which way it needs
to read the collisionData

2) Update MeshToMeshCD to properly populate data
based on 1.

To geometries, objects, collision data

Still need to connect callbacks to retrieve collision data.

Adds time integrator which only sets rules for finite difference in time.
Adds comments for DeformableObject class

1) Clean up print methods
2) Put initialize, print, clear, getVolume on top
3) Add missing overrides
4) Replace extractSurfaceMesh by computeAttachedSurfaceMesh
5) Define Mesh::print
6) Use Mesh::clear in subclasses

Adds a function to check if a geometry is a mesh.
Adds printing to geometry class
Stylistic changes in extract mesh class

Adds Tetra-Triangular mesh map.
TODO: Code check and add tests

Use config based on https://gist.github.com/mkroman/1372117

Also remove headers in cmake files

Uses a dummy implementation of imstkScene to test
a module execution in multithreading.

Adding project name (iMSTK)

Skeleton of CMake architecture and of first few classes.