sowm: Window splitting

[Unixsys]

 * Add keybinds for splitting windows
  - Use vim keybinds with Win+Alt
  - Example: Win+Alt+h will split the window to the left


  - Note: this patch will *not* snap windows to corners of the screen.

Patch: https://patch-diff.githubusercontent.com/raw/dylanaraps/sowm/pull/76.patch
Requested from issue #75.

[dylanaraps]

You will have to structure the PR like the others. See #57

[dylanaraps]

This looks great though, thanks!

[Unixsys]

Stylistic issues fixed. Let me know if there's anything further I can do. Sorry for the late response. Might want to close issue #75, as it requested this PR.

[dylanaraps]

👍

[remysucre]

A small trick I found: splitting full-screen windows gets you closer to actual tiling, as it also prevents the mouse from moving / resizing windows out of place.

[Unixsys]

@remysucre This is exactly how I use this patch.

[remysucre]

Me too :) In fact, would you consider adding if (!cur->f) win_fs(arg); right before win_size in win_half? That pretty much creates a "tiling mode" whenever cur->f is true.

[Unixsys]

I'm not going to add that, due to some people (me included) don't like all windows fullscreen all the time. However, thanks for your suggestion! :D

[serenevoid]

I have tried extending the splitting functionality with gaps since a lot of people like myself love to have gaps (or useless gaps from dwm).

#113