collapse command output virtually instead of using regions

[lunixbochs]

if we actually delete the hidden lines, the sublime buffer shouldn't jump
maybe "running the command" again un-collapses the lines, with a syntax hint to allow re-collapsing using the sidebar
not many other good options

[lunixbochs]

woah that's a great way to do tty integration too...

initial command output is a legit tty. if you click inside, context forces keybindings for terminal input
at 24 lines we eat old lines for free because we're a real terminal
if you "re-run" the context, it will unwrap... or maybe offer a command to open the command's output in a new tab?