Feature request: Fix cascading error messages

[Christopher Heckman]

I have a request concerning Lilypond that has bothered me for a while,
but which I haven't seen any one else complain about. It is the
cascade of error messages you get when you leave out a right-brace or
some other symbol.

Maybe this could be added as an option to lilypond?

lilypond --cascade-level=N file.ly

which, for any given line, prints the first N error messages, and
after that a message saying that further error messages have been
suppressed. A default value for N might be 3 or 4.

What does everyone think?

--- Christopher Heckman