fix src/commands.c with clang-format
feature: implement ewmh desktop viewport property

Set and update the _NET_DESKTOP_VIEWPORT property

http://standards.freedesktop.org/wm-spec/wm-spec-latest.html#idm140146176862048

> _NET_DESKTOP_VIEWPORT x, y, CARDINAL[][2]/32
> Array of pairs of cardinals that define the top left corner of each
> desktop's viewport.
Workspace command number selection

If a `workspace {N}` or `move to workspace {N}` command is given with N
as a plain number, the workspace of this number is selected for the
context of the command if one exists and there is no workspace with a
name that exactly matches N.