Make all vectors non-ghosted except current_solution. Removed many compress(insert) since they are not needed. Solution is saved in directory output. Removed const qualifier on output_results since the Timer does not work.
Initial condition for Pk seems to work. Renamed some local variables. Formatted screen output.
In positivity limiter modify solution only if theta1 or theta2 is < 1.0
Modify solution only if theta < 1.0
Merge positivity limiter with TVB limiter. Needs to be tested.
Fixed initial condition for Pk case.
Updated limiter for Pk case.
Replaced cell_number function to use user_index
Adding new minmax limiter for unstructured grid
min and max of cell average should include current cell. Add check for du < 0 since if du=0 then we get divide by zero.
Adding characteristic limiter for minmax. Needs to be tested.
Remove update_values from cell assembly since we dont need this.
Merge branch 'master' of https://github.com/juanpablogallego/dflo

Conflicts:
	src_mpi/assemble_explicit.cc
	src_mpi/claw.cc
	src_mpi/ic.cc
	src_mpi/output.cc