factor out scalebox()

May switch to the version from sway if that seems like a good idea at
some point.

note about cursor init

configure monitor rotation/reflection

add chvt function

It truly isn't just a window manager anymore :-|

make space for window borders

change cursor during move and resize

style in buttonpress

simplify move/resizemouse functions

funnel all resizing through resize()

use exit code macros everywhere

some comments and reminders

factor out renderclients

This will help once we get to implementing layer-shell

don't autoraise

Still raise in buttonpress and focusstack of course.  Focus models
honestly wouldn't be too hard to make into a config.h option.

use the focus stack to determine stacking order

Suddenly we have autoraise!

adopt a bit more dwm-like terseness

change focus(NULL, NULL) to mean unfocus

"Focus the most recently focused window on selmon" is now refocus()

implement focusmon and tagmon

focus follows mouse

add incnmaster and setmfact commands

add toggletag and toggleview