[FOLLOWUP][TASK] Add missing documentation for feature #31100

This patch adds the missing documentation.

Resolves: #69406
Related: #31100
Releases: master
Change-Id: Ifff18e4e9ec9750fe1d686decd88857cc4b13c57
Reviewed-on: http://review.typo3.org/42920

Reviewed-by: Andreas Fernandez <typo3@scripting-base.de>
Tested-by: Andreas Fernandez <typo3@scripting-base.de>
Reviewed-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Tested-by: Anja Leichsenring <aleichsenring@ab-softlab.de>

typo3/sysext/core/Documentation/Changelog/master/Feature-31100-IntegrateMultilineSupportForTEXTBLOCKInFormWizard.rst

+==========================================================================
+Feature: #31100 - Integrate multiline support for TEXTBLOCK in form wizard
+==========================================================================
+
+Description
+===========
+
+The form object TEXTBLOCK is now rendered as multiline input field in the form wizard. Line breaks are automatically converted to <br>
+tags in the wizard preview and the frontend.