Feature request: Evaluate multi-line selection

[Sohalt]

It would be cool to be able to evaluate all currently selected lines. This would be especially helpful when collaborating with multiple people on a single Sonic Pi file, because it would allow selectively making changes to individual live_loops without having to wait for everyone to get their code to a safe state.

[Qirky]

I've added a multi-line selection evaluate but will evaluate all the lines the selection is on, not just the selected text :+1:

[Sohalt]

Cool! Thank you!