[natmch]: New feature to power cycle an individual AMC slot
4 new methods added to the NATMCHTelnet class.
- _get_slot_state: Internal method to get the current state of the AMC in a given slot. {M1, M2, ..., M7}
- _stop_slot: Internal method to power down the AMC in a given slot.
- _start_slot: Internal method to power up the AMC in a given slot.
- reboot_slot: Top-level method that combines _stop_slot and _start_slot to power cycle the AMC in a given slot.