Add ePIC UMC miner support

[taserz]

Fixes #10.

Adds scanner, configurator, and rebooter support for ePIC UMC miners using the v3 REST/JSON API running on port 4028.

Scanner (scanner/EpicUmc.lua):

• Reads /summary to populate pool URLs/workers/passwords from StratumConfigs, average hashrate (MH/s converted to TH/s), per-hashboard temperatures from HBs, fan speed from Fans, and software version
• Reads /capabilities for the model name, setting the full type string to ePIC <Model> (e.g. ePIC SC200) or ePIC UMC as a fallback
• Stores the current coin from Mining.Coin in epic.coin for use by the configurator

Configurator (configurator/EpicUmc.lua):

• Posts the pool configuration to /coin in the format the v3 API expects: {"param": {"coin": ..., "stratum_configs": [...], "unique_id": false}, "password": ...}
• Uses the coin stored by the scanner or defaults to BTC if not present
• Looks up the admin password via utils.getMinerLoginPassword('EpicUmc')

Rebooter (rebooter/EpicUmc.lua):

• Posts to /reboot with {"param": 0, "password": ...}
• Polls /summary on port 4028 every 5 seconds (up to 30 attempts) until the device responds, matching the pattern used by other rebooters

Detection (scanner/HttpAutoDetect.lua):

• When port 80 is unreachable or returns an unrecognized response, the detector now probes port 4028 with a GET /summary request
• If the response contains both Hostname and Session fields the device is identified as an ePIC miner and the EpicUmc executor is launched
• If port 4028 also yields nothing, the existing fallback to GenericCgminerApi runs as before

ScannerHelper.lua, ConfiguratorHelper.lua, and RebooterHelper.lua are updated to require the new scripts.