Porting GRC to Electrum

[nathanielcwm]

gridcoin-community/Gridcoin-Research#953

@Quezacoatl1 recommended porting Gridcoin to Electrum as a hardware wallet port was promised by @TheCharlatan if it was ported.

This could probably attract people who might be interested in Gridcoin but don't want to run the standard wallet or put their coins in the hands of coinomi, holytransaction, wallet bot or the exchanges.

However, this will likely take a lot of work and maintenance.

[jamescowens]

This is effectively requires the completion of the bountied GUI redo..., gridcoin-community/Gridcoin-Research#847, gridcoin-community/Gridcoin-Research#1401, because this is not tenable without separating the wallet more cleanly between the core and the GUI. Then we can have more than one GUI front end.