Tutorial example for creating an assembly of cylinders

Running the simulation: 

- To run the simulation:
  ./Allrun.sh

- To clean-up the directory after the simulation is run: 
  ./Allclean.sh

- To view eMesh files in paraview:
  ./readEmesh.sh

- Assembly generation parameters are set in ./system/searchableSurfacesDict

- "searchableSurfacesList" (list of searchable surfaces) and "eMeshesList" (list
   of eMeshes) is included in ./system/snappyHexMeshDict

- "includeForcesFiles" (list of force function objects for post-processing) is
  included in ./system/controlDict
