More robust flcbdfWrappers, linear algebra

* Adds more tests around flcbdfWrappers communicator usage
* Also improves linear algebra norm tests
* Linear algebra tests are not designed to run in parallel yet
@cekees - I believe we could change this line to PETSC_COMM_WORLD and get the correct default behavior of the global communicator being initialized.  I don't know if you think it's worth giving this a try.