pjonworker now completely obsolete
Add new Pinboard-dump URL source.
Support for multiple workers and subset captures.
Many bug fixes and enhancements to pj-trace-redir.js.

 * window.open() is trapped and the child page instrumented; requests are
   logged, and console messages can no longer escape.
 * Can now capture HTML content without also capturing a screen shot.
 * No longer confused by subsidiary HTML pages loaded into iframes.
 * Correctly handle window.location changes from script executed
   synchronously during page load (i.e. before onLoadFinished fires).
 * Redirection counts are now accurate.
 * Network logs included unconditionally in output.
Simple script to dump out capture logs for analysis.