Change I9b649aafba011d537e3fe4eebef7a678ff6733e4 has added a
compute API to trigger crash dump in instance. This patch adds
the REST API to nova. It enables users to trigger crash dump in
an instance through REST API.
Change-Id: I6ed777ff637254b4b79417008f9055dd19fc7405
Implements: blueprint instance-crash-dump
Co-Authored-By: Hironori Shiina <shiina.hironori@jp.fujitsu.com>
Co-Authored-By: Tang Chen <tangchen@cn.fujitsu.com>