[FEATURE] Allow setting of validation messages in form editor

Add the form element property "validationErrorMessages" to allow the
definition of custom validation error messages with the help of the
form editor.

Resolves: #80124
Releases: master
Change-Id: Ic72a5adf0a943a0fae11eb4af89c66f7fa6ca00f
Reviewed-on: https://review.typo3.org/52078


Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Tobi Kretschmann <tobi@tobishome.de>
Reviewed-by: Steffen Frese <steffenf14@gmail.com>
Reviewed-by: Alexander Opitz <opitz.alexander@googlemail.com>
Tested-by: Alexander Opitz <opitz.alexander@googlemail.com>
Reviewed-by: Susanne Moog <susanne.moog@typo3.org>
Tested-by: Susanne Moog <susanne.moog@typo3.org>