Transient code. Uses DMComposite. Nothing works.
GR in progress
Initial attempt at refactoring code. Not complete yet.
Refactoring still in process.
Refactoring still in process.
Merge branch 'refactored_code' of https://github.com/mchandra/grim into refactored_code

Conflicts:
	boundary.h
	boundary/boundary.h
	geometry.h
	geometry/geometry.h
	physics.h
	physics/physics.c
	physics/physics.h
	riemannsolver.c
	riemannsolver/riemannsolver.c
	src/boundary/boundary.h
	src/geometry/geometry.h
	src/physics/physics.h
	src/riemannsolver/riemannsolver.c
Added cmake files.
Added .gitignore. More code added. Not complete yet.
Unified EXPLICIT, IMEX and IMPLICIT time stepping into a single residual
function. Lots of code clean up everywhere. Still need to add wavespeeds,
constraint transport and floors.
Timestepper library finally compiles (commented out the calls to riemannsolver).
Added riemannsolver and constraint transport code. Code compiles. Still need to
add in floors and diagnostic monitors.
Touched up build system. Fixed INDEX_* calls to accept only pointers to zone
struct.
Removed coordinates.c and initialconditions.c. Will put them back later in a
proper problem framework.
Started to populate problems.
Cleaning up the problem folder and worked on magnetized_field_loop_advection_2d.
Added various diagnostics. First trial run. Weird memory error possibly in
initialConditions().
Fixed indexing in INDEX_LOCAL and replaced DMDAVecGetArray with VecGetArray
because DMDAVecArray gives *data for a 1D array and **data for a 2D array
whereas we want a 1D array always irrespective of COMPUTE_DIM. Hence we use
VecGetArray.
Various bug fixes. Still need to fix SNES linesearch diverges.
Fixed errors in the IMPLICIT code.
Added required libraries to CMake inside the problem folder. Else compilation fails.