This PR is a stab at allowing toctree entries to contain relative links (#701) by allowing hyperlinks.

Currently, toctree's allow explicit web links via a special syntax that looks like

.. toctree::

    intro
    Some title <http://www.google.com>         <- special syntax

but replacing the explicit web link with a relative one "../some/path" results in sphinx trying to find a document and failing. Essentially, plain relative links can't be added in a toctree.

One suggestion in #701 was a special syntax <href:../some/path>. However, after looking over the code, it seems cleaner to support standard rst inline hyperlinks.

.. toctree::

    `Some title <any/link>`_
    `<title/will/be/this/link>`_

Just like inline hyperlinks in text, If no title is explicitly given, the link text is used as the title (i.e. body of the anchor tag). Separately defined .. _a link: http://example.com/ target's aren't supported though.

I'd mostly just like to see #701 addressed, whether it is this approach or something else the maintainers like.