Fix spelling of OpenStack in the project descriptions of Gerrit

According to the OpenStack Documentation conventions it should
be OpenStack and not Openstack or openstack.

https://wiki.openstack.org/wiki/Documentation/Conventions#OpenStack.2C_not_Openstack_or_openstack

Change-Id: I43b2510393c8fc231fbc99b935a8b994b1569f8e
Merge "Fix spelling of OpenStack in the project descriptions of Gerrit"