PIG-4250: Fix Security Risks found by Coverity

git-svn-id: https://svn.apache.org/repos/asf/pig/trunk@1635868 13f79535-47bb-0310-9956-ffa450edef68
PIG-4160: Provide a way to pass local jars in pig.additional.jars when using a remote url for a script

git-svn-id: https://svn.apache.org/repos/asf/pig/trunk@1635875 13f79535-47bb-0310-9956-ffa450edef68
PIG-4259: Fix few issues related to Union, CROSS and auto parallelism in Tez (rohini)

git-svn-id: https://svn.apache.org/repos/asf/pig/trunk@1635880 13f79535-47bb-0310-9956-ffa450edef68
PIG-4182: e2e tests Scripting_[1-12] fail on Windows

git-svn-id: https://svn.apache.org/repos/asf/pig/trunk@1635893 13f79535-47bb-0310-9956-ffa450edef68