Merge pull request #7860 from localheinz/feature/validate

Enhancement: Validate composer.json on Travis

.travis.yml

@@ -38,6 +38,7 @@ before_install:
   # disable default memory limit
   - export INI=~/.phpenv/versions/$(phpenv version-name)/etc/conf.d/travis.ini
   - echo memory_limit = -1 >> $INI
+  - composer validate
 
 install:
   # flags to pass to install