- Fixed last data point for sensor which was throwing an error when no data was found instead of returning None
- Added index on sensor data created date to speed up "latest data point" queries on sensors
- Added ordering by name for sensors
- Optimized sensor loading in admin and in dashboard by recording the last value in the sensor model itself
- Added json dictionary of extra arguments for sensor cards. The "timeout" key/value can now be specified as the timeout for the connection