runMUI now with Record Selection syntax

Following the change to UISF, Euterpea's runMUI now uses a default
UIParams value (defaultMUIParams) which can be updated with record
syntax as needed.  runMUI' uses the default value.
NOTE: This will break most current code, but the update is
straightforward.  Replace
> runMUI size title
with
> runMUI (defaultMUIParams {uiSize=size, uiTitle=title})
NOTE ALSO: MUI examples from the HSoM chapter on MUIs have been
commented out instead of updated -- that chapter needs to be almost
entirely rewritten anyway, and I will get to that later.