Allow LilyPond to automatically handle then end of a staff with \partial

[Tom Dickson]

A feature I would like is to make it so that barchecks don't fail on  
the end of a staff started with \partial. Especially in songs, the  
last measure will usually be cut down by the same amount as the  
\partial at the beginning. Currently I have to hide the time signature  
and change time at the end of the staff to make it look right.

Other than that Lilypond has worked wonderfully for our booklet we're  
making. Thanks!

-tom