Dovecot documentation

[@lbutlr]

the make config options for dovecot on FreeBSD list list  

	[x] ICU             Use libicu for FTS unicode normalization

but https://wiki2.dovecot.org/Plugins/FTS makes no mention of libicu (nor of icu at all).

is linicu simply in addition to the four options of Solar, Lucene, fts-xapian, and fts-dovecot?

Also, the link to fts-dovecot goes to https://wiki2.dovecot.org/Plugins/FTS/Dovecot which is a 404.

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