Feature/pod maintenance

Module::Build has "testcover" "testpod" and "testpodcoverage" targets already.  I suggest we use these, instead of writing unit tests to do the same.

This set of commits will:

- Add targets in top makefile, which again run the */Build files with appropriate options 

- Remove test files which do this already.  This removes the "style and documentation" checks from unit tests, which check if the code runs as it should.