[FEATURE] Configurable IP-Mask for statisticWriter (anonymize)

Provides the possibility to use

plugin.tx_solr.statistics.anonymizeIP = 1 # Number of octets to reset

Resolves: #53235
Releases: 3.0
Change-Id: Ic6af8592a008726dfe1262d00d1e85d0c033d481
Reviewed-on: https://review.typo3.org/25583
Reviewed-by: Ingo Renner
Tested-by: Ingo Renner