Relax API restrictions around the use of reboot

Fixes bug 1101082 bug 982108

Reboots are the only sledge hammer users have available to resolve
issues with their instances without administrative intervention.
This patch modifies the API policy to allow reboot calls to be made
in many more power and task states.

Change-Id: Ia8702448f6b7b863da40e4d498f2e2ee0a12882e
Merge "Relax API restrictions around the use of reboot"
Imported Translations from Transifex

Change-Id: Ideb135261b0f9b2c32b118e7dd033809a14acdcd