Support Arbitrary Pane Layouts

It already supports arbitrary layouts; it's just missing the split commands to generate them.

So is there any way to use them, currently? The only way I see is to select one of the "layouts" and then to drag files to them.

There are keyboard shortcuts to move files to different pane numbers, but no shortcuts to move them, say, right a pane. I don't think doing this is actually possible at the moment, because while you can set arbitrary layouts I believe there's still no way to read back what the current layout is.

If you check out your Main.sublime-menu you can see how the layouts are actually created.

To clarify: With the Cmd-T vim plugin, I can start searching for a file (like Sublime's Goto Anything command) and then split it into a vertical or horizontal pane. This pane sticks with that tab. So I can look at a model and its test side-by-side, but when I switch to a controller the next tab over, I see it and its test, instead of needing to switch each pane separately.