Removes MANIFEST.in as it is not needed explicitely by PBR
Removes MANIFEST.in as it is not needed explicitely by PBR

This patch removes `MANIFEST.in` file as pbr generates a sensible
manifest from git files and some standard files and it removes
the need for an explicit `MANIFEST.in` file.

Change-Id: Idcb810f3bb7adc281ee400333e10247b93f3a4d9

stackforge/akanda-appliance,openstack/akanda-appliance,stackforge/akanda-appliance,openstack/akanda-appliance