Fixed the phpdoc of the Doctrine ORM adapter
Improved the code of the DBAL adapters

- Fixed a typo in the private method name
- Added a typehint on the function argument
Merge pull request #147 from stof/patch-2

Fixed the phpdoc of the Doctrine ORM adapter
Fixed coding standards
Merge pull request #148 from stof/fix_cs

Fix coding standards
Merge pull request #149 from stof/typehint_query_builder

Improved the code of the DBAL adapters
Merge pull request #150 from stof/simplify_travis

Simplified the Travis build matrix
Added testing on HHVM
Made HHVM use dev versions of dependencies

Doctrine DBAL stable is not compatible with HHVM. Only the 2.5 version
is but it is not yet stable.
Disallow failures on HHVM