Let the framework be able to override the hostname.

The hostname is passed in during the server installation. We should use
this hostname for the resulting server as well. It was being discarded
and we always used the system hostname value.

Important changes:
- configure ipa_hostname in sssd on masters
- set PKI_HOSTNAME so the hostname is passed to dogtag installer
- set the hostname when doing ldapi binds

This also reorders some things in the dogtag installer to eliminate an
unnecessary restart. We were restarting the service twice in a row with
very little time in between and this could result in a slew of reported
errors, though the server installed ok.

ticket 1052

ipalib/config.py

@@ -447,7 +447,6 @@ class Env(object):
         self.__doing('_bootstrap')
 
         # Set run-time variables (cannot be overridden):
-        self.host = getfqdn()
         self.ipalib = path.dirname(path.abspath(__file__))
         self.site_packages = path.dirname(self.ipalib)
         self.script = path.abspath(sys.argv[0])
@@ -550,9 +549,6 @@ class Env(object):
         if 'log' not in self:
             self.log = self._join('logdir', '%s.log' % self.context)
 
-        # FIXME: move into ca plugin
-        if 'ca_host' not in self:
-            self.ca_host = self.host
         self._merge(**defaults)
 
     def _finalize(self, **lastchance):