Internationalization for public errors

Currently, we throw many public exceptions without proper i18n.
Wrap natural-language error messages in _() so they can be translated.

In the service plugin, raise NotFound errors using handle_not_found helper
so the error message contains the offending service.

Use ScriptError instead of NotFoundError in bindinstance install.

https://fedorahosted.org/freeipa/ticket/1953

ipaserver/plugins/join.py

@@ -106,7 +106,7 @@ class join(Command):
             # It exists, can we write the password attributes?
             allowed = ldap.can_write(dn, 'krblastpwdchange')
             if not allowed:
-                raise errors.ACIError(info="Insufficient 'write' privilege to the 'krbLastPwdChange' attribute of entry '%s'." % dn)
+                raise errors.ACIError(info=_("Insufficient 'write' privilege to the 'krbLastPwdChange' attribute of entry '%s'.") % dn)
 
             kw = {'fqdn': hostname, 'all': True}
             attrs_list = api.Command['host_show'](**kw)['result']

ipaserver/plugins/selfsign.py

@@ -208,7 +208,8 @@ class ra(rabase.rabase):
             serial = x509.get_serial_number(cert)
         except NSPRError, e:
             self.log.error('Unable to decode certificate in entry: %s' % str(e))
-            raise errors.CertificateOperationError(error='Unable to decode certificate in entry: %s' % str(e))
+            raise errors.CertificateOperationError(
+                error=_('Unable to decode certificate in entry: %s') % str(e))
 
         # To make it look like dogtag return just the base64 data.
         cert = cert.replace('\n','')