Revert "Removed dropConnection migration."

This reverts commit 270179c9d6488de3cda934299a447883bb0ca949.
Partially revert "Removed everything relating to deprecated feature: 'connections.'"

This partially reverts This reverts commit 7db85238eca136c599dd6e45386e125c4580dc86.
Fixed Austin's migration.

Note that normally, I wouldn't edit a migraiton file after it had been
committed, but this is to fix a prior mistake that was caused from
doing just that.