Update the documentation on sourceURL
There should be no functional changes in this CL

R=ssaviano
DELTA=31 (15 added, 5 deleted, 11 changed)


Revision created by MOE tool push_codebase.
MOE_MIGRATION=6146


git-svn-id: http://closure-library.googlecode.com/svn/trunk@2441 0b95b8e8-c90f-11de-9d4f-f947ee5921c8