Enable custom fuel stream urls

[jp0550]

Enable custom fuel stream url per our conversation on community.webcore.co to enable custom (local) urls to be sent to the UI.

Tested for backwards compatibility for both UI and backend.

Hubitat's version will have something like this in the getFuelStreamUrl's method

return [
		list : [l: true, u: baseUrl + "intf/fuelstreams/list?access_token=${state.accessToken}"],
                get  : [l: true, u: baseUrl + "intf/fuelstreams/get?id={fuelStreamId}&access_token=${state.accessToken}", p: 'fuelStreamId']
    ]