Removed explicit dependency of LiipImagineBundle

As it's already a dependency of ezpublish-kernel...

Author: lolautruche

composer.json

@@ -34,7 +34,6 @@
         "hautelook/templated-uri-bundle": "~1.0 | ~2.0",
         "doctrine/dbal": "~2.5@rc",
         "doctrine/doctrine-bundle": "~1.3@beta",
-        "liip/imagine-bundle": "~1.0",
         "symfony/expression-language": "~2.4",
         "sensio/framework-extra-bundle": "~3.0"
     },