docs: commit message format section correction

Signed-off-by: Adrian-Tudor Panescu <adrian.tudor.panescu@cern.ch>
Merge remote-tracking branch 'adrianp-github/pu' into pu
restful: fix registry loading

Signed-off-by: Jiri Kuncar <jiri.kuncar@cern.ch>
requirements: dictdiffer egg fix

Signed-off-by: Adrian-Tudor Panescu <adrian.tudor.panescu@cern.ch>
JSONAlchemy: allow `extend` on parser extension

* Allow to extend the content of the parser extensions, like for the
  producer rules.

Signed-off-by: Esteban J. G. Gabancho <esteban.gabancho@cern.ch>
JSONAlchemy: bug fixes
JSONAlchmey: improvements in the model handling
WIP