minor #1352 Updated the Travis CI configuration (javiereguiluz)
minor #1352 Updated the Travis CI configuration (javiereguiluz)

This PR was squashed before being merged into the master branch (closes #1352).

Discussion
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Updated the Travis CI configuration

We do this from time to time copying the latest changes introduced by Symfony: https://github.com/symfony/symfony/blob/master/.travis.yml

Commits
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1ae4ba6 Updated the Travis CI configuration

OskarStark/EasyAdminBundle,javiereguiluz/EasyAdminBundle,yceruto/EasyAdminBundle,yceruto/EasyAdminBundle,yceruto/EasyAdminBundle,OskarStark/EasyAdminBundle,OskarStark/EasyAdminBundle,javiereguiluz/EasyAdminBundle