Update Django version to 1.4.13
Merge pull request #873 from quamilek/develop

Update Django version to 1.4.13
Update scan.rst
Fixed Review
Update scan.rst
Migrations ordered
Merge pull request #875 from zefciu/migration-merge

Migrations ordered
Merge pull request #874 from vi4m/docs_fixes

Documentation for scan provided.
CHANGELOG updated
Merge pull request #876 from zefciu/develop

CHANGELOG updated
Merge branch 'develop' of https://github.com/allegro/ralph into quickscan
Changelog updated.