Bugfix: In redmine 2.3.1.stable, the path to the svg file was absolute but didn't include the path to redmine's root. This meant one would get "/graphs/target-version/1" instead of "/redmine/graphs/target-version/1". This commit fixes the bug by prepending Redmine::Utils.relative_url_root .
Merge pull request #1 from jsmaniac/master

Bugfix: path to the svg is absolute but doesn't include redmine's root