Avoid redundant info message during RPM update

A change to ipa-ldap-updater (and thus an RPM update %post scriptlet)
avoiding redundat "IPA is not configured" message in stderr introdocued
in c20d4c71b8 was reverted in another
patch (b5c1ce88a4).

Return the change back to avoid this message during every RPM update
when IPA is not configured. admintool framework was also fixed to
avoid print an empty line when an exception without an error message
is raised.

https://fedorahosted.org/freeipa/ticket/2892

ipapython/admintool.py

@@ -212,7 +212,8 @@ class AdminTool(object):
             self.log
         except AttributeError:
             # Logging was not set up yet
-            print >> sys.stderr, '\n', error_message
+            if error_message:
+                print >> sys.stderr, '\n', error_message
         else:
             self.info(''.join(traceback.format_tb(backtrace)))
             self.info('The %s command failed, exception: %s: %s',

ipaserver/install/ipa_ldap_updater.py

@@ -25,6 +25,7 @@
 # save undo files?
 
 import os
+import sys
 
 import krbV
 
@@ -83,10 +84,14 @@ class LDAPUpdater(admintool.AdminTool):
                 raise admintool.ScriptError("%s: file not found" % filename)
 
         if os.getegid() == 0:
-            installutils.check_server_configuration()
+            try:
+                installutils.check_server_configuration()
+            except RuntimeError, e:
+                print unicode(e)
+                sys.exit(1)
         elif not os.path.exists('/etc/ipa/default.conf'):
-            raise admintool.ScriptError(
-                "IPA is not configured on this system.")
+            print "IPA is not configured on this system."
+            sys.exit(1)
 
         if options.password:
             pw = ipautil.template_file(options.password, [])