Fix issues on CentOS.

1. On CentOS django 1.4.9 is used, that breaks new-style urls (full
support in django 1.5).

2. Also we have different murano-repository config on Fuel
installation, that also caused a bug due to hardcode in
murano-dashboard.

Change-Id: Ice4324c258330e790a51954c4ade58ba3fd7c6bc