Add missing registers

[canton7]

31010	11015	EPS RVolt	2376	237.6 V	int16	0.1	V	voltage
31011	11016	EPS RCurrent	2	0.2 A	int16	0.1	A	current
31012	11017	EPS RPower	3	0.003 kW	int16	0.001	kW	power

From StealthChesnut/HA-FoxESS-Modbus#112 (comment)

[FozzieUK]

If you don't have EPS it's more registers to add, more to poll (thinking the slow W610) and more to exclude from your database to avoid bloat.

I would rather see an option in the config for 'Add EPS sensors?' than add the sensors, but it's a lot more work, more complexity and tbh I would rather have them than not so feel free to ignore this comment.

[canton7]

Yeah... I would eventually like to get to a point where the user could disable a sensor, and we would stop polling for it. Then we could have sensors which are disabled by default, and the user could enable them if they wanted.

[canton7]

I've also found:

10016: master version
10017: slave version
10018: manager version

[canton7]

EPS implemented in #167, versions covered by #176