Implement 'personality' plugin for V2.1

User can specify 'personality' attribute while server creation
& rebuild to inject files into server.

This patch implement this as separate plugin for V2.1 API.

Also define the schema and unit tests for the same.

Partially implements blueprint v2-on-v3-api

Change-Id: Ia0c527539af7fe33eba4999822476653e1b96bc6
objects: introduce numa objects

This work is a prerequisite to convert VirtNUMAHostTopology
and VirtNUMATopologyCellUsage to objects

Change-Id: I6cafb1954f93a185fc9f570ee6091d75769075f4
objects: move numa host and cell to objects

To continue objectification of numa, this commit move
numa host/cell related to objects.

Change-Id: I9fbc3ed6d9bd74840e42586faa9951d9672691c1
Merge "objects: introduce numa objects"
Merge "objects: move numa host and cell to objects"
Merge "Implement 'personality' plugin for V2.1"