Update README.md

Add required libraries to installation instructions.
dd# Untracked files:
Updated time zones and email debugs
Update README.md

Corrected spelling
PS on line 50 - there is not a spot to edit the email and password in sw_checkin_email.py. SHould that be edit default_settings.py ?
Update README.md

Moved install notes for Ubuntu 12 to bottom
Added note about Gmail two factor auth.
Merge pull request #18 from dcjones21/master

Time Zone Update for international