Using grey for average.
Merge branch 'master' into NAWQAAN-122

Conflicts:
	nar_ui/views.py
Switched order of average and current year bars. Accounted for different year ranges.
Making units metric
Checkpointing attempts to group graphs by unit label.
Merge branch 'master' into NAWQAAN-122
Tweaks.
Merge pull request #35 from cschroed-usgs/NAWQAAN-122

Nawqaan 122