* vc/log-view.el: Header fix.
* vc/log-view.el: Doc fix.
* maintaining.texi (Branches): Add motivations for branching.
Refine docs of VC.

* maintaining.texi (VC Mode Line): Fix typo.
(VC Directory Commands): Mention `vc-dir-hide-up-to-date' with
prefix argument.
Modify `log-view-mode-map'.

* vc/log-view.el (log-view-mode-map): Copy keymap from
  `special-mode-map'.
Merge from mainline.
Some fix for VC.