Fix warnings
connectivity_is_valid: allow floating corners/edges
Update refine semantics
Add callback_orphans parameter to coarsen_ext
Extend test_coarsen
Use P4EST_ALLOC instead of SC in wrap
Makeover of p4est_wrap

The user_data field of the p4est quadrants is no longer used.
Refinement and coarsening is now implemented with the new mark_refine
and _coarsen functions.
The wrap_refine function has been renamed to wrap_adapt.
Assertions and flag reset
Define ghost members and functions for exachange
Remove some waitall statuses
Tweak existing ghost code
Move p4est_add_ghost_to_buf down in file
Populate ghost mirror data
Require contiguous data for ghost exchange
Implement ghost exchange function
Write test for ghost exchange
The ghost exchange seems to work
Merge remote-tracking branch 'github/wrap' into cbdev
Merge remote-tracking branch 'ices/ghost2' into cbdev
Write wrap_get_ghost and _mesh