Add HTML help button
Initial help listener
Rudimentary marker color change on help button click
github practice; small modification to teams.on()
Change icon color

When the field ‘needsHelp’ changed in the database, change the icon’s
color accordingly.
Merge branch 'help' of https://github.com/ryanluo/hub into help

Conflicts:
	app/static/js/firebase_interface.js
	app/static/js/map_interface.js
Introduced button toggles and code clean up for help branch
Merge branch 'master' of https://github.com/ryanluo/hub