In a consensus reached in a proposal for code review process
change [1], and proposed team structure policy document [2],
adding MAINTAINERS files in repositories.
Please note, that this file is written in YAML format in order
to allow further automation around code review process.
[1] http://lists.openstack.org/pipermail/openstack-dev/2015-August/072406.html
[2] https://review.openstack.org/#/c/225376/1
Change-Id: I54c2ad8f36e88570ad545968933474fc207acc75