10b1b39478
Suppose a horizontally oriented workspace has two windows open. Issuing "split h" on the right window creates a nested horizontal container. If we now resize in "width" direction, the resize doesn't work because it will only operate on the current parent, which is a container with only one child, so the resize command exits. This is unexpected behavior from a user point of view. Hence, with this patch, we ensure that we don't just go up the tree until we find a parent with the correct orientation, but also keep going if that parent has only a single child. fixes #2015
