Implement unittests for report lists.

Spot a bug and fix it.
Add a unittest for txscapy.
Fix oonibclient tests.
Make it possible to run ooniprobe also without having dnet installed.
Print out the options that are missing.
No collector means no collector.
Handle the case where no command is specified.
Add extra checks in the body and header comparisons
Don't start tor if no collector option is specified and no test helper is needed.
Fix problem in starting Tor when no test helper is set.
Reformat README.md so that it uses syntax common to markdown and rst.
Convert README to rst
Update LICENSE and expand setup.py
Convert changelog to rst.
Update MANIFEST
Update README
Add back OONI logo
Improve REAMDE formatting.
Fix Changelog reading in setup.py
Fix rst formatting.