Integrate possibility to override TCA columns depending on the type by another TCA property
Currently it's possible to override field properties of existing TCA columns by using Page TSconfig. Settings, depending on the type of a record, can be overridden if that property was allowed to be overridden.
This issue is concerning the possibility to do basically the same, but in TCA (not in Page TSconfig) and also for properties that were not allowed to be overridden.
The following example re-uses the image field of tt_content and defines that only one image could be added:
$TCA['tt_content']['types'][$_EXTKEY.'_pi1']['overrideColumns'] = array(
'image' => array('config' => array('maxitems' => 1)),
(issue imported from #M6365)