start to add support for nose testing framework
clean up the test structure.

All tests should now be in a tests/ folder and should be compatible with
nose
move some more tests into nose framework
move pele.application to obsolete
finish setting up the nose testing framework

remove file run_tests.py
forgot to add a test
say how to run tests in README
Install more test modules and data files used by the tests.
Travis-CI test file.