[BUGFIX] Property mapping config for TYPO3 6.1

The property mapper was updated in TYPO3 / Extbase 6.1 (see #47182)
it is required to explicitly specify the properties that are allowed
to be mapped.

Resolves: #55993
Change-Id: Ia44c2ed5d735e9f20c7a270275f23313411fc501
[BUGFIX] Prevent PHP warnings in initial marker hook

To prevent warnings in the initial marker TCA hook the data property in
the MarkerBase class is casted to an array.

Resolves: #55990
Change-Id: Ib92fed52c5cfd899293d9de6bc6d1a13100ba1c3