Revert "Try adding Docker caching for Travis CI"
Revert "Try adding Docker caching for Travis CI"

This reverts commit 1990efdba7fe16723940eb119d9b2fc11c7eda41.

IngoHeimbach/ale,w0rp/ale,hernot/ale,hernot/ale,neersighted/ale,neersighted/ale,IngoHeimbach/ale,hernot/ale,neersighted/ale,w0rp/ale,IngoHeimbach/ale,w0rp/ale