PIG-3497: JobControlCompiler should only do reducer estimation when the job has a reduce phase (amatsukawa via aniket486)

git-svn-id: https://svn.apache.org/repos/asf/pig/trunk@1529075 13f79535-47bb-0310-9956-ffa450edef68
Merge remote branch 'origin/trunk' into trunk
Merge remote branch 'origin/trunk' into trunk-gd