Enable irregular barlines

[reinierdevalk]

Barlines in tabulature can be irregular, even though the mensuration does not change. We should have the flexibility to deal with this.

Example:
phalese-1547_7-no_21.png

[DILewis]

I think we'd generally expect to use barLine rather than <measure> in this case? That should be fine with irregular barring. Or is there something I'm missing?

[lpugin]

Yes. Nothing particular here as far as I can tell.

[reinierdevalk]

Ah, I didn't know/forgot I knew. Then this issue can be closed again.