* changes to unit-tests/test_functions_PhageTerm_for_multi.test_checkpoint_creation() accommodating that the first read is now considered. e.g. total match length goes from 291333 --> 291441 due to first read length of 108.
* minor restructure of unit tests to include standard setUp() and tearDown() methods, simplifying the creation/deletion of tmp dirs. This means that the unit tests don't fail if they detect leftover tmp directories leftover from a previous run that didn't cleanup because it failed.

I was having trouble with some pieces of code related to relative paths
etc., and tracked some issues to hard-coded paths and then to the lack
of a setUp/tearDown procedure in test_functions_PhageTerm_for_multi.py.
I did some refactoring to make them a little easier to use and a little easier to extend.

work in progress: trying to find a more compact way to store readsCoverage results on disk to save place in multi machine mode