Merge pull request #25 from ansell/master

Remove Quad, not in scope at this point. Fixes #8
updated diagram as result of issues #8 and #25
provided some background about the discussion at issue #24
configured maven-license-plugin (issue #28)
switched to other maven-license-plugin (issue #28)
added commons-parent as parent (issue #28)
switched to other maven-license-plugin (issue #28)
added missing parameter (issue #28)
switched to yet-another maven-license-plugin (issue #28)
added license header (fixes issue #28)