replace all occurrences of findEntitesChangedAtRevision with findEntitiesChangedAtRevision
make backward compatible.
Merge pull request #42 from caxy/fix-findEntitesChangedAtRevision-typo

replace all occurrences of findEntitesChangedAtRevision with findEntitie...
Update AuditReader.php
Update .travis.yml
Check if there's any entity modification before updating