Doc update: title right click resizes floating windows

Long description:

This documentation update describes the change implemented in
905440d6d1c6d2a872e3bbb0da4c963bedaf5708
It avoids repetitive usage of the word 'also'.

To apply this patch, use:
curl http://cr.i3wm.org/patch/410/raw.patch | git am

@@ -166,7 +166,8 @@ hint and are opened in floating mode by default.

 You can toggle floating mode for a window by pressing +$mod+Shift+Space+. By

 dragging the window’s titlebar with your mouse you can move the window

 around. By grabbing the borders and moving them you can resize the window. You

-can also do that by using the <<floating_modifier>>.

+can also do that by using the <<floating_modifier>>. Another way to resize

+floating windows using the mouse is to right-click on the titlebar and drag.

 For resizing floating windows with your keyboard, see <<resizingconfig>>.