[TYPO3-mvc] Validators should allow empty values

[Dennis Ahrens]

Hi list,

i've started the backport of the change in FLOW3 [1] and ask myself if 
the validators in extbase still have to return boolean values for 
backwards compatibility or if they should behave like in FLOW3 (@return 
void)

regards
Dennis

[1] 
http://git.typo3.org/FLOW3/Packages/TYPO3.FLOW3.git?a=commitdiff;h=9b627954f289d793b808db2ac19edc6a04c25426;hp=5572609a0e9a5087a1185e3c0b30227c4618345d