Update beam grouping rules
treeabffbf55e0f86c54e7b726e0584c73df6957d40f
drwxr-xr-x - bin
drwxr-xr-x - doc
drwxr-xr-x - etc
drwxr-xr-x - lib
-rw-r--r-- 2433 main.ly
drwxr-xr-x - out
drwxr-xr-x - scores
drwxr-xr-x - share