Closed #9 added day/night graph, and shift list. added default values.

analytics.tpl:
Split everything into a table, added a backgruond colour.

dbinterface.py:
added a function which grabs userName based on UserID. slightly useless
I know but there are situations where it is handy.

webclient.py:
Added code to set default values of dates if none are selected.
Currently, if no dates are selected, it grabs the last 30 days. If you
populate a start_date then it grabs from then to today. If you only set
an end date, it grabs from a month before that end date. Also now shows
the user name in analytics page.