This commit lets the 'move' command apply to floating containers as well
as tiled ones. The command may be appended with a number of pixels and
then optionally the string `px` (like '10 px') in order to move the
container more or fewer than the standard ten pixels.
- added L_AUTO_FIRST/LAST instead of using explicit layouts.
- when switching between auto layout that don't share the same major axis, invert the
width/height of their child views to preserve their relative proportions.
Drew DeVault
Calvin Lee
wil