Testing on all installed versions of lilypond

[noteflakes]

Add --all option to lyp test command to run package/local tests on all installed versions of lilypond.

Also, the lyp test command should normally not display the lilypond output (both STDOUT and STDERR) unless the --verbose option is given. It should however count assertions (displayed in test files by calling #(assert:summary)) and show a summary of the tests:

• Any failures (file/package/lilypond version)
• Number of assertions per package, total assertions
• Total running time