Gauges -> Counters

[Psykar]

Some of the gauges you've set up seem better represented as counters (eg. M_Imported M_Exported AC_Energy_WH )Would a PR to change these to counters be accepted? I'm not entirely sure if it would be backwards compatible is all.

While we're at it, what are your thoughts on changing the SunSpec fieldnames to be labels instead of the metric name itself? That would enable easier querying of all the currents for example Current{job="solaredge"} instead of having to do things like {__name__="*.Current.*",job="solaredge"}? This one definitely would be breaking obviously.