Add barline at start of music

[craigsapp]

Here is a command that lists scores that do not start the music with a barline (from the humdrum directory:

grep -r -B 1 -m 1 ^= . | grep -v ":.*=" | grep -v -- "-\!" | grep -v -- -- | grep -v "krn-\*"

No scores have a missing first barline.

There were probably fixed previously with the bin/fixBarnus script used in conjunction with make fb. I change barnum to barnum -a so that cases as in issue #10 do not happen (not labeling overfull measure with bar number).