Setting metric unit declaratively.
Refactored a bit the setMetricUnit invoker.
Implemented the onMinusClick declaratively. Requires a refreshView which
flashes all previews and works only the first time.
Implemented the onValueTextChange declaratively.
Fixed a bug with bounded value.
Firing minRangeReached.
Do not allow non numeric values.
Declaratively setting style to minus on minRangeReached.
Setting preview text declaratively.
Some code clean-up and JSLinting.