It is now possible to create "Import" records in TYPO3 system.
Those records can then be imported via two new commands.
There is no need to configure everything within the command itself.
That allows:
* To allow editors to maintain import configuration.
* Have proper labels, description, csh and UI to create import.
It no longer is necessary to copy UIDs,
instead proper wizards from TCA are available to select pages.
Relates: #9649
Add new record type partner.
This can be something like a media partner or something else.
Allow an event to have zero or more partner.
Add necessary files and models with relations.
Relates: #8092
