docTypes and aknDocTypes config

[kohsah]

Currently this configuration is duplicated across the editor-ui and editor-fe.

It needs to be retrieved from the editor-fe by the editor-ui.

Editor-ui currently:

• aknDocTypes.json - akoma ntoso root doc types
• docTypes.json - docTypes with subTypes supported by this editor implementation

Editor-fe currently:

• docTypes.json - identical to aknDocTypes.json (above).

To Fix:

move aknDocTypes.json into editor-fe (i.e. rename editor-fe docTypes.json to aknDocTypes.json and delete aknDocTypes.json from editor-ui)

move docTypes.json out of editor-ui into editor-fe

Make editor-ui retrieve aknDocTypes.json and docTypes.json from the editor-fe server