Run tests on travis ci
travis: install requirements and run mailpile-test
travis: don't use requirements.txt
travis: use direct link for GnuPGInterface
travis: drop py2.5 as we can't run self-test there now
travis: make pep8 less strict now
Nose tests, track coverage, don't do pep8 and pyflakes
tests: TestUI: better log messages verification
tests: updated search tests
tests: remove help_variables, not available anymore
tests: some folders in /tmp might be inaccessible, use tests
test_command: test_index should check that message is 'OK'
tests: updated test for new settings keys and API
tests: update as_text test
test_search: updated count comparison
Use requirements.txt while installing dependencies on travis