Revert "travis-ci: Trying to migrate to container-based infrastructure."
Revert "travis-ci: Trying to migrate to container-based infrastructure."

This reverts commit 2825cd2dde71bd1ca8517c5823f1361384004b8a.

bh107/bohrium,bh107/bohrium,madsbk/bohrium,bh107/bohrium,madsbk/bohrium,bh107/bohrium,madsbk/bohrium,madsbk/bohrium