replace settings[idx_blahdeblah] ?

[penfold42]

With some of the changes recently I've tried to use bits sparingly.

As a result there's some pretty ugly bit masking/shifting scattered through ui.cpp. Should we ditch the settings array and replace it with an extended rx_settings struct ? I suspect we'd need a working copy in ui:: that the config menus can fiddle with.

Then we can shift all the bit-shifting and stuffing into the autosave/recall functions. And probably do some input validation while we're at it.

grep 'settings\[' ui.cpp | wc -l
145

Its a stack of work, but I'm up for it. Thoughts?