Add support for Fronius 3 phase inverter and Smart Meter 63A-3

[sudoc]

Support for Fronius 3 phase inverter and Fronius 3 phase Smart Meter Proposed changes are tested on Fronius Symo *.0-3 M inverter (highest possible firmware) with Smart Meter 63A-3, but there is also possibility to use only one of them (for example only inverter without Smart Meter).

Fronius API does not gives all information divided to 3 phases, so such data is attached to first phase (anyway, sum counts correctly).

[klew]

Please comment if you plan to address above comments.