Update duped user check, stats collection, perl version detection, other minor fixes.

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UPDATED - Modify existing Ensim-only duplicate username check to run for any panel, and also print any trueuserdomains entries that do not have unique first 8 username characters (11.44 requirement):

Requested By:
  Forest Kistner

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FIXED - Misspelled the ssp-requests email address in the stats-submission stuff which was printed if an error was to be reported.

Credit:
  Blaine Motsinger

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UPDATED - HTTP status codes changed on the stats collection server, update to handle new status codes and also make the handling more generic for future server status code changes.

Requested By:
  Chris Borsheim

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FIXED - Perl version detection method replaced with one that worked on every perl version I could test with.  Previous check was mis-firing on some versions of Perl.

Credit:
  Richard Asp
  Kyle Pinkley

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ADDED - Add output_buffering to the php.ini options that are compared on source and dest servers.  A difference here can break scripts that rely on output buffering to be enabled globally without explicitly enabling it in the script.

Requested By:
  Brian Dial

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UPDATED - Migration blocker notices.  Added case 107517 for Ensim, removed case 72981.  Removed case 97657 for DA.

Requested By:
  Richard Asp

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