Rework timestamps so that each timestamp records two times: an arrival time/departure time.  Integrate new timestamps into database.  Separate help into a sub-module separate from the sidebar sub-module.  Add instructions and help to every page, including 'Back to Tutorial' button on /start page and 'Reset' button on /start page.
Pre-merge commit.
Merge branch 'master' into production

Conflicts:
	dowsing-js