The hotline information has been shortened to

datetime opened,
zip code,
longitude,
latitude,
case#

The datetime now conforms to the formats in existing csv (change
to 2400 and dashes for date rather than slashes).

I am unsure of the convention used for placing these files into
folders, so I will change relative paths after someone else does
this.

For now, 'python hotline.py' will open 'Mayor_s_24_Hour_Hotline__
Service_Requests.csv', find cases which had been opened after
2014-03-01, between 10pm-3am, find the missing zipcode, format
the datetime, and write the above columns into 'hotline.csv'