Create toggle for utc/local time

This commit deals with the rickshaw code, using helpers from
graphs/util.js for standard/stacked

Yet to address horizon graphs`
Fix spec to match new button name
Cleanup post spec search. More comments, less console
Merge branch 'ui-fixes' into utc-time
Merge branch 'utc-time' of github.com:anchor/machiavelli into utc-time

Conflicts:
	app/views/partial/navbar/_clock_changer.html.erb