* Added checks to make ci for yaml linting
* Modified y(a)ml files to pass lint checks

Problem was caused by facts not being set for that master. To fix this
patch cleans up the calculation of metricsPublicURL in general. Because
this value is used in openshift_master to template into the master
config file, we now define these facts more clearly in
openshift_master_facts, and add a dependency on this to
openshift_metrics.

The calculation of default sub-domain is also changed to remove it from
system facts (as neither of these are facts about the system) and
instead use plain variables.

Some applications expect the *_PROXY variables to be lower case.
To support this too inject them in addition to the upper case ones.

Signed-off-by: Pascal Bach <pascal.bach@siemens.com>
Reviewed-by: Fabio Huser <fabio.huser@siemens.com>

Configures HTTP_PROXY, HTTPS_PROXY, NO_PROXY for master and docker services.
Configugres BuildDefaults Admission controller for master to automatically
insert proxy environment configuration into build environments.

To use set at least these variables
  - openshift_http_proxy
  - openshift_https_proxy

NO_PROXY entries will automatically be configured for hostnames of all openshift
hosts. You may specify additional NO_PROXY hosts or patterns by setting
`openshift_no_proxy`

If you wish to disable automatic generation of NO_PROXY hosts you may set
`openshift_generate_no_proxy_hosts` to False.

If you wish to have different builddefaults proxy configuration than baseline
proxy configuration set these variables
  - openshift_builddefaults_http_proxy
  - openshift_builddefaults_https_proxy
  - openshift_builddefaults_no_proxy
  - openshift_builddefaults_git_http_proxy
  - openshift_builddefaults_git_https_proxy