[merge request] add-window-matcher, bugfix, doc.

[Teika Kazura <teika lavabit com>]

Hi. Please merge my branch. It includes:
* Minor bug fix in move-resize.jl
* Doc, including news.
* add/remove-window-matcher improvements.

An example of the new grammar for add-window-matcher is:
(add-window-matcher '((WM_NAME . "^root$")
                      (WM_CLASS . "^XTerm/xterm$"))
                    '((ignore-program-position . t)
                      (maximize . vertical)))

Following Timo's suggestion, the actions are passed as an alist.
(Thanks!)

The old usage is still possible, but it is deprecated.
In fact, it was not only powerless, but buggy.  Suppose you've got
rules for '((WM_NAME "foo") (WM_CLASS "class")) and '((WM_NAME "bar")
(WM_CLASS "class")), i.e. the class is common. Now if you do
(add-window-matcher 'WM_CLASS "class" actions...), then it will be
added to *one of* the above two, and it's unpredictable which will be!

Regardless of which syntax is used, the old buggy match is avoided.

viewport-offset-pixel is planned to be renamed to
viewport-offset-coord, but not yet done in this .

Regards,
Teika (Teika kazura)