[FEATURE] Switch View Helper

Simple view helper that allows you to render content depending
on a given value or expression.
It bahaves similar to a basic switch statement in PHP.

Usage:

<f:switch expression="{person.gender}">
  <f:case value="male">Mr.</f:case>
  <f:case value="female">Mrs.</f:case>
</f:switch>

Change-Id: I44a7066dfa86785f795069e0f06391cb45fa373c
Resolves: #48653
Releases: 6.2
Reviewed-on: https://review.typo3.org/21155
Reviewed-by: Alexander Schnitzler
Tested-by: Alexander Schnitzler
Reviewed-by: Jigal van Hemert
Tested-by: Jigal van Hemert
Reviewed-by: Felix Kopp
Tested-by: Felix Kopp