Bump keystone wsgi props and make configurable

In MOS we're using formula, but it should be more or less always correct to
have 6/3 for CCP:
https://github.com/openstack/fuel-library/blob/master/deployment/puppet/openstack_tasks/manifests/keystone/keystone.pp#L154-L155

Change-Id: Iaa19c607c614f9b14426d3d2771333cc29fef989

service/files/defaults.yaml

@@ -13,6 +13,9 @@ configs:
 
   keystone_debug: false
 
+  keystone_wsgi_processes: 6
+  keystone_wsgi_threads: 3
+
 sources:
   openstack/keystone:
     git_url: https://github.com/openstack/keystone.git

service/files/wsgi-keystone.conf.j2

@@ -3,7 +3,7 @@ Listen {{ keystone_public_port }}
 Listen {{ keystone_admin_port }}
 
 <VirtualHost *:{{ keystone_public_port }}>
-    WSGIDaemonProcess keystone-public processes=5 threads=1 user=keystone group=keystone display-name=%{GROUP} python-path={{ venv_path }}
+    WSGIDaemonProcess keystone-public processes={{ keystone_wsgi_processes }} threads={{ keystone_wsgi_threads }} user=keystone group=keystone display-name=%{GROUP} python-path={{ venv_path }}
     WSGIProcessGroup keystone-public
     WSGIScriptAlias / /var/www/cgi-bin/keystone/main
     WSGIApplicationGroup %{GLOBAL}