Removed "Thx to XYZ from CHANGELOG.md"

* Changelog is for announcing changes
* Attributions are in git log, or even at https://github.com/forkcms/forkcms/contributors
* The most active contributors were not even mentionned
remove references and comments copied from the blog module
Merge pull request #466 from WouterSioen/faq-comments2

remove references and comments copied from the blog module
Merge pull request #462 from matthiasmullie/master

Removed "Thx to XYZ from CHANGELOG.md"
make use of deleteThumbnails function in the blog module
Keep get parameters when rewriting backend url
Merge pull request #476 from DoFken/patch-11

Keep get parameters when rewriting backend url
Merge pull request #474 from guytarded/deleteThumbnails

make use of deleteThumbnails function in the blog module