enabling a prefix for communication (should really refactor the subdomain comm
at some point)
Using a callback function for the prefix instead of a string
Specifying that the comm_args passed to local time stepper should be of type
bfam_subdomain_comm_args_t
Removing the RK stuff for now, since I don't know how to use it yer
Starting to add a prefix callback function
Setting up for the send and recv use rates when they are supposed to