Add news item for 0.7.3
Update links for the next release

I removed all references to Google Code (except for the issue tracker), and
also links to packages on other systems, which was an out-dated page.
Merge pull request #65 from asmeurer/release

Update links for the next release
Merge branch 'master' into redesign

Conflicts:
	cs/index.html
	de/index.html
	en/index.html
	es/index.html
	fr/index.html
	pt/index.html
	ru/index.html
	templates/index.html
	zh/index.html