Update Advanced Use of the JIRA Issue Collector documentation

The documentation that instructs how to add more than one Issue Collector to a single HTML page is not updated.

There were some code typos that would prevent customers to follow the page.

I've updated the JIRA 6.3 version of the page: https://confluence.atlassian.com/display/JIRA063/Advanced+Use+of+the+JIRA+Issue+Collector

And the Full Source Code section there is right and will work. Could you make sure its updated across all versions that have this page?