Change URLs for widgets

We need to follow same scheme as in translation URLs, otherwise it's
hard to decode same. So use / as separator instead of - as - is valid
character in project name and can lead to bad matching.

The old URLs remain valid, but will not be presented to users.

Fixes #531.

Signed-off-by: Michal Čihař <michal@cihar.com>
Merge branch 'master' into bootstrap
Fix displaying of git revisions

Signed-off-by: Michal Čihař <michal@cihar.com>
Merge branch 'master' into bootstrap

Conflicts:
	weblate/html/git-commit-info.html