Introduce service base class and clean up ipa-server-install

1) Add a base class for all of the instance objects.
2) Normalize usage of logging.
3) General cleanups of ipa-server-install.
4) Make better use of httpinstance.
5) Add webguiinstance.
6) Improve progress reporting during installation.

Works Here (TM), but it would be nice to get someone else
to test since this moves code around a bit.

ipa-server/ipa-install/share/Makefile.am

@@ -19,6 +19,7 @@ app_DATA =				\
 	krbrealm.con.template		\
 	ntp.conf.server.template 	\
 	radius.radiusd.conf.template	\
+	referint-conf.ldif		\
 	$(NULL)
 
 EXTRA_DIST =				\