pki-setup should be run regardless of token provider

The puppet-keystone module currently will only execute
'keystone-manage pki_setup' to create the signing key if the PKI
token provider is being used. The signing key/cert is still used
for signing the token revocation list, even when the UUID token
provider is being used. We should be running
'keystone-manage pki_setup' if enable_pki_setup=true, regardless
of token provider.

Change-Id: I2817fbde74cbd50cae31f681503816e576cc7b60
Closes-bug: #1373064
setup keystone using apache mod_wsgi

Allow keystone to be set up to use apache mod_wsgi as the server
instead of a standalone eventlet service.  There is a new keystone
class parameter: service_name.  The default is 'keystone', which will
set up the standalone eventlet service.  If 'httpd' is used, the
keystone class will skip creating the keystone service, which also means
no 'openstack-keystone' service.  The class 'keystone::wsgi::apache' is
then used to configure apache mod_wsgi to serve keystone.

Had to remove the File resource default in the keystone class.  When
using wsgi::apache, the apache class and other classes are included.
Since puppet uses dynamic scoping, this overrides the file resources
in those classes as well.  keystone now explicitly sets all of the
parameters in files/directory resources.

Change-Id: Ib05ac81381e169845b44b2ef7cb810a4d5db17de
Closes-Bug: #1348728