HAProxy exposes a Prometheus metrics endpoint, it just needs to be
enabled. Enable this and remove configuration for
prometheus-haproxy-exporter. Remaining prometheus-haproxy-exporter
containers will automatically be removed.

Change-Id: If6e75691d2a996b06a9b95cb0aae772db54389fb
Co-Authored-By: Matt Anson <matta@stackhpc.com>

There are inconsitencies across the documentation and the source code files
when it comes to project's name (Kolla Ansible vs. Kolla-Ansible). This
commit aims at unifying it so that the naming becomes consistent everywhere.

Change-Id: I903b2e08f5458b1a1abc4af3abefe20b66c23a54

Describes the proposed approach to introduce Prometheus monitoring
for Kolla-Ansible deployment.

Partially-Implements: blueprint prometheus
Change-Id: I54616925abb76bda7efa2f2ae962d4e43f097551