Move markup control panel to CMFPlone for #220

Obsoletes: https://github.com/plone/Products.CMFPlone/pull/257
Closes https://github.com/plone/Products.CMFPlone/issues/220

This is the follow-up of @djay 's pull-req #257 . i adapted his work to fit into the newer controlpanel structure. i squashed down everything into two commits: @djay 's original one and my fixes.

NOT READY YET, as we have make fixes in the following packages:
- plone.app.upgrade
- plone.app.textfield
- Products.Archetypes and/or Products.ATContentTypes