Add shortest path to test set.
Fix right connectivity test.
Make pagerank tests run again.
Fix all tests.
Allow data files to be run along program files.
Initial MPI setup
Support recursive functions.
Add function class.
Improve debugging code and remove some old syntax from tests.
Generate inbound in the data file instead.
Simplify heat transfer program.
Add new case when moving to stack.
Add new DEBUG_INSTRS directive.
Make desc priority be the default priority. Print priority information in print_predicates.
Update test byte code.
Add get_stack_at method and use it.
Make heat transfer data files compilable as data files.
Add basic MPI code that works for 1 process

`make test-linear` passes when either running mpi with 1 process or without
mpi.
Temporary Commit
Debug commit