AI-844 : added sorting support to site.adminEntity
AI-844 : sorting may not be set (at least in tests, avoid NPE)
AI-844 : fixed parameter injection
AI-844 : added test for sites sorting by adminname (levels -> E1, E2,...)
Merged in hotfix/AI-844 (pull request #2)

AI-844 : hotfix (avoid issue with sql parameter injection)