Flood Sensor Firmware for CubeCell Dev-board plus - First Release

Tested the beta release, and patched duty-cycle update bugs.

New Features:

1. fw_ver is added to the CFG update. The firmware version set using this variable is a constant and can be modified only on a flash.
2. sensor_statedefines the state of the sensor operation. Three possible states are:

• Start Sensing
• Stop Sensing, CFG packets are uplinks
• Reset, uses the watchdog timer to soft reset the MCU

3. CFG state has a duty cycle of 10s, for convenience in the field during deployments
4. After every state change, the uplink packet is the new CFG and is updated after every state change including reset (doesn't work with resets due to brownouts).

Changes:

1. TX_INTERVAL is the sensor_sleep, and units are seconds
2. appTxDutyCycle is the current duty cycle - varies based on state, and is in milliseconds.

Full Changelog: v4.0.0...v4.0.1