Limit thermostat setpoint range ("child proofing")

[climategadgets]

Current Behavior

Setpoint change will be allowed to happen as long as the setpoint is set within absolute "sane" thermostat setpoint limits. This allows unreasonable values set either accidentally, or by individuals not comprehending how the system works, which causes the system run beyond its design capacity and cause a massive electric bill and runtime overrun.

Desired Behavior

• Setpoint range can be specified individually per zone in the configuration
• Setpoint range can be specified in the schedule event description
• Setpoint range override should still be available via JMX and to individuals authorized to make changes beyond provided setpoint range

[climategadgets]

Setpoint range in configuration was introduced in #183, now need to extend it to schedule and JMX.

[climategadgets]

Implemented in the configuration as part of #47