Push this as 0.99, after PEP 440 pushed pip to ignore pre-releases.

There are no significant changes in this compared with 1.0b3 (the
only changes are documentation/testsuite related).
Increment version number after 0.99 (provisionally 0.999).
Remove the isstring hack in lxml treewalker.

This fixes #115 as a result, as we're no longer type-sniffing strings.
Fix #127, add a work-around for CPython bug 20007.

The bug has been fixed upstream, but this works around it
on older Python versions.
This does not change any behavior on Python versions with the fix.
Add changelog for recently changed things.
Drop -dev from version number for release
And back to dev for 0.9999.
Stop using --use-mirrors when installing requirements.

--use-mirrors both found mirrors and accessed them insecurely, yet
trusted them (CVE-2013-5123); pip 1.5 removes support.
Installing flake8 separately is unnecessary; it is in requirements-test.txt.
Allow Genshi to be installed insecurely, for now.

Ergh. It's not like there's not been masses of warning about this.
Add a documentEncoding property to HTML5Parser, fix #121.
Fix #146; fix all pep8 1.5.4 failures
Merge branch 'master' into sanitizer-fixes-72

Conflicts:
	CHANGES.rst
	html5lib/sanitizer.py