Feature: move space to other monitors

[jtaala]

This PR resolves #824.

It adds the following:

• keybinds (Ctrl+Alt+left/right/up/down) which moves the current workspace to a different monitor in that direction;
• if a workspace is the last on a monitor, we fallback to swapping that space with the target monitor space;
• informs user with notification if can't move / swap a space;
• FIXES Second monitor doesn't have tiling/Crash #816 by creating spaces to meet a minimum (i.e. PaperWM breaks if have 2 monitors and only one space...);

[Lythenas]

As far as I can tell this works fine.

Are you sure you want to use these keybindings? I don't really use it that often but e.g. in gimp ctrl+alt+arrow moves the selection. I imagine in other graphical programs this does something similar. Not sure if that is a big deal.

[jtaala]

As far as I can tell this works fine.

Are you sure you want to use these keybindings? I don't really use it that often but e.g. in gimp ctrl+alt+arrow moves the selection. I imagine in other graphical programs this does something similar. Not sure if that is a big deal.

Good pickup. Yes, that would be confusing for sure (go to move selection in gimp and you move the workspace to another monitor...). Any suggestions for alternate keybinds?

I was trying to keep some relation to the swap keybinds (alt+super+...).

What about Ctrl+Super+left/right/up/down? can't do them since they clash with move window to monitor keybinds...

What about

• Ctrl+Alt+Shift+left/right/up/down?

Dang, running out of keybinds...

[Lythenas]

Ctrl+Alt+Shift+left/right/up/down?

That is probably fine.

I would also be fine with not having default keybindings, but then the feature might be hard to discover.