Timezone fix

This should fix the time displays in all the views (and perhaps resolve the other issues #497 and #498?).  

What I found was that the time_zone on the initial user record was nil (even though it displayed the current system setting timezone-- as it should).  So change just actually makes the system time zone effective when there is no user or the user hasn't selected a time zone.

I also found that when setting the start_time and end_time that it was assuming utc and then shifting it for your time zone, so when you set it to start at midnight, it actually shifted it to 9 am (in my zone).  So I changed it to parse it as local time, so midnight means midnight your time, not utc time.

Please give it a whirl in your zone before merging.  Thanks.