Modified code to make a bit more generic and extendable

Specifically:
- Created an array called garages with all the garage pins in it
- Made a generic 'toggleGarage' agent callback that will be called
  whenever we're toggling a garage
- Made toggleGarage set pin high for 1 second, then set it low again
- Removed imp.configure in the device code, as it's a deprecated method
  and no longer required