PIG-3426: Add support for removing s3 files

git-svn-id: https://svn.apache.org/repos/asf/pig/trunk@1521207 13f79535-47bb-0310-9956-ffa450edef68
PIG-3426: Add support for removing s3 files

git-svn-id: https://svn.apache.org/repos/asf/pig/trunk@1521211 13f79535-47bb-0310-9956-ffa450edef68
PIG-3430: Add xml format for explaining MapReduce Plan.

git-svn-id: https://svn.apache.org/repos/asf/pig/trunk@1521214 13f79535-47bb-0310-9956-ffa450edef68
PIG-3431: Return more information for parsing related exceptions.

git-svn-id: https://svn.apache.org/repos/asf/pig/trunk@1521216 13f79535-47bb-0310-9956-ffa450edef68
PIG-3431: Return more information for parsing related exceptions.

git-svn-id: https://svn.apache.org/repos/asf/pig/trunk@1521222 13f79535-47bb-0310-9956-ffa450edef68
Merge remote branch 'origin/trunk' into trunk