Reorder actions for faster brew day

[dseidman]

Refill the HLT during the mash step rather than before it. Where HLT and MLT are different vessels, only fill the HLT to strike water volume so mashing can start sooner - heat all the strike water after mashing has begun. Start heating the kettle as soon as a min kettle volume is achieved rather than waiting for the sparge to finish. Except the change in strike volume, which is purely good (except if there is a short mash time, large HLT and slow HLT heating, which should be quite rare), these may need to be configured by options.