Disable ServerSignature and Hide apache related infromation.

Change-Id: I9188ddb85988539087c922117bb9f53454b7507c

Apache access log formats are modified to be consistent with
the format defined in wsgi-keystone.conf, which includes
the response time (%D) and X-forwarder-For fields.

Change-Id: I02aa5eb106fb894196dfb6e22daf2968e27ed3cb
Closes-Bug: #1703571

Trace method is enabled in default for httpd. There is security risk
with trace enabled. So disable it in default. more info please check[0].

[0] https://security.stackexchange.com/a/7711

Change-Id: I4496a6d058d88e1abfb210085f189e7a610e0362
Closes-Bug: #1705160

* use gnocchi-api script for wsgi based on this commit[0].
* logfile is deprecated. Use log-file instead[1].

[0] https://github.com/gnocchixyz/gnocchi/commit/c8717e8b71f044953aec744f44f97abad1a0c08e
[1] https://github.com/gnocchixyz/gnocchi/blob/master/gnocchi/opts.py#L77,L82

Change-Id: I8fbe8425e43d82e0f9601ba6303dd7f24142a2e6

Useful api_interface_address variable has been define here:
https://github.com/openstack/kolla-ansible/blob/master/ansible/group_vars/all.yml#L57
In order to simplify codebase we must use it as much as possible.

Change-Id: I18fec19bf69e05a22a4142a9cd1165eccd022455

TrivialFix

Change-Id: Ibbfb214749340454d68ee009a4f90da88fa0d831

* mount gnocchi volume for gnocchi-api and gnocchi-statsd
* fix the failed of gnocchi-api
* use gnocchi user when running gnocchi-upgrade
* use the app.wsgi file in python path directly, rather than copy it to
  /var/www/cgi-bin/gnocchi/app file

TrivialFix

Change-Id: Ie026b8f44cd8e9703bf115cebb4e2d50b114a3a2

Partially-Implements: blueprint ansible-gnocchi

Change-Id: I8dd0460bd21ac0a233fab0142ec7b6079459bdc2

Partially-Implements: blueprint ansible-aodh

Change-Id: I9e20f4bf5e7d8f37f243ae15746e2b7bb49eb20c