Revert "Move getLocalStream() and getRemoteStream() to prototype"
Revert "Move getLocalStream() and getRemoteStream() to prototype"

This reverts commit 6dda4f22a8524e3b9a4f88ef3ba8e12014ae105c.

Change-Id: I087a4df2507b118dc54c63d59552258736cc08fc

shelsonjava/kurento-utils-js,lcamacho/kurento-utils-js,shelsonjava/kurento-utils-js,lcamacho/kurento-utils-js