* Clean up help text * Fix confusing error when nonexistent source_set provided.
* Clean up help text
* Fix confusing error when nonexistent source_set provided.


git-svn-id: 55198a34599dbf839a02c2a2ff0bd06dff76438e@275 960bbd1a-3921-0410-93bb-a35bc832efea

google/mysql-tools,google/mysql-tools