Split TemplateCJM into its own dist

  TemplateCJM now distributed as Dist-Zilla-Plugin-TemplateCJM
  Bump version of dist to 4.20
Reformat Changes to match spec
Fix Test::PrereqsFromMeta to handle empty hash

  For some reason, I got a META.json with '"recommended": {}' in it.
  That shouldn't happen, but it's not hard to handle.
  Bump version to 4.20
Updated Changes for August 24, 2013 release of 4.20