PIG-3112: Errors and lacks in document "User Defined Functions" (miyakawataku via cheolsoo)


git-svn-id: https://svn.apache.org/repos/asf/pig/trunk@1427570 13f79535-47bb-0310-9956-ffa450edef68
Merge branch 'trunk' of https://github.com/apache/pig into trunk