Driver updates (I2C, I/O expander, CO2)
Separated test functions
Soil irrigation control

. Added soil irrigation control (in progress)
. Added archive of non-SMB I2C communication lib for CO2 driver
. Added I/O Expander driver (no interrupt support)
Added server monitoring & email alerting script
allowed fractional minutes and seconds for --pause --timeout
updated alert.py to produce reports and alert on pH changes
Bug fixes
Added env to ignored directories
Merge branch 'master' into feature/pylons
Web application is componentized, zone aware, and uses JSON configuration. TODO: re-connect to real data.