Updated opensprinkler library with version that allows access to the rain
sensor state.
Changed OpenSprinkler to an Active Binding. Added ability to update state
on stations from the OpenSprinkler device regularly. Added Contact item
type for rain sensor.
Added default for OpenSprinkler refresh rate to the default config.
Removed redundand conditional.
Merge pull request #1534 from CrackerStealth/opensprinklerenhance

OpenSprinkler Enhancements