Fix encoding for setattr/addattr/delattr

Attribute values passed by --{set,add,del}attr parameters were
normalized and validated using appropriate parameter, but were
never encoded for the backend. This make prevents manipulation
with dirsvr BOOL attributes where framework tries to pass
boolean value instead of encoded "TRUE"/"FALSE" values.

https://fedorahosted.org/freeipa/ticket/2418

ipalib/plugins/baseldap.py

@@ -782,6 +782,8 @@ last, after all sets and adds."""),
                 except errors.ValidationError, err:
                     (name, error) = str(err.strerror).split(':')
                     raise errors.ValidationError(name=attr, error=error)
+                if self.api.env.in_server:
+                    value = self.params[attr].encode(value)
             if append and attr in newdict:
                 if type(value) in (tuple,):
                     newdict[attr] += list(value)