translatable findOneBy repository method
Added translatable QueryBuilder with common query building logic
Add hidden select only when ordering by conditional expression
Added optional  parameter to QueryBuilder's and TranslatableRepository's methods
Throw exception when invalid join type is passed
Merge pull request #45 from chives/dev

Translatable QueryBuilder with common query building logic, TranslatableRepository findTranslatable*() methods
Added php 5.6 and hhvm to travis build matrix
Merge pull request #46 from chives/dev

Added php 5.6 and hhvm to travis build matrix
Updated dev dependincies
Increased code coverage by tests
TranslatableListener heavy refactor
Fixed renumbering file if already exists