We ultimately decided to provide a limited set of devices in exec/java
drivers instead of all of host ones.  Pre-0.9, we made all host devices
available to exec tasks accidentally, yet most applications only use a
small subset, and this choice limits our ability to restrict/isolate GPU
and other devices.

Starting with 0.9, by default, we only provide the same subset of
devices Docker provides, and allow users to provide more devices as
needed on case-by-case basis.

This reverts commit 5805c64a.
This reverts commit ff9a4a17.