magit-log: add forward compatibility kludge
README.md: shorten feature freeze notice
README.md: remove unused link urls
README.md: add prominent links to the FAQ and the Roadmap
CONTRIBUTE.md: concentrate on the feature freeze and the roadmap
README.md: remove tarball and marmalade instructions

Using a tarball is no longer a supported installation method.  We
will continue to provide a tarball for distributions but users who
do not use their distributions native package manager, are strongly
recommended to use Elpa instead.

We will continue to make new releases available on Marmalade, and
once 2.1.0 has been released the README will once more explain how
to do so.
Merge branch 'master' into next

Conflicts:
	README.md
	magit.el
README.md: improve wording
README.md: the other package is VC, not Version Control

From `(emacs)Version Control`:

  The Emacs version control interface is called "VC".