Added ckeditor stable as a submodule to htdocs/js/ckeditor

Added a gitignore so that the files generated by the setup script don't
get added to the repo in future.
Also included the the cached template folder 'template_c' so that
doesn't get included either

 Changes to be committed:
	new file:   .gitignore
	new file:   .gitmodules
	new file:   htdocs/js/ckeditor