Revert "Test gevent"

This reverts commit fa84b1e795ea6dae89a4617da81bad0b9655af02.
Revert "Test greenlet"

This reverts commit 6945f4c7d1a468fda8246cb381031be97d8af308.
Revert "Test greenlet"

This reverts commit ada32e3bc1c986ab7a8116f45b14f568bbb8c343.
Revert "Test greenlet"

This reverts commit 65bdd9a976362c30e7dbd8b5e53a26966681eac4.
Revert "Test with greenlet"

This reverts commit e276fcd767ef89817d9ff25077094d349b930ff2.