Refactoring the dgx communicator filling (i.e., seperating out the filling from
the interpolation)
Reducing duplication of the copy to the glue
Making it so that the user can call the glue fill routines by passing a null
pointer to the comm put send function
Convenience function for adding rates to all comm fields
missing paren (after some rebase)
Local time stepping (mostly) working. Still need to test extensively, add RK
initialization, make it so that glue fields are sent through the communicator
with local time stepping.