Improve shutdown of pFUnit tests in MAPL

[tclune]

pFUnit supports EXTRA_INITIALIZE and EXTRA_FINALIZE for global resources that will be used in the tests.

Currently MAPL/pfunit/MAPL_Initialize.F90 starts up a few global resources:

• ESMF
• pflogger
• udunits

But there really should be a corresponding finalize that shuts these down (esp ESMF).

The task is to (1) create that routine and (2) modify the cmake macros that use MAPL_Initialize to also use the new finalize.

One option is to rename the host module for MAPL_initialize to be init/final and then put both routines in there. Easier to keep symmetric. Alternatively create a new module, but then the EXTRA_USE argument also needs to know the new module.