WL#8987: Add the ICU library to handle RLIKE/REGEXP.

Affects: Server-8.0   —   Status: Complete

There have been requests from customers about a REGEXP_REPLACE function. It is the #2 requested feature of all time, behind only CTEs: BUG#27389 - regular expression substitute. This bug is also duplicated in BUG#79428, BUG#29781, BUG#16357, BUG#9105

There are smaller requests for additional features:

BUG#29590 - Support for back-references (0 affected, 2 subscribed) BUG#8098 - REGEX match count (0 a, 2 s) BUG#70413 - \d is not working in REGEXP for a MySQL query (1a, 5s) BUG#68271 - allow for reverse regex (0a, 1s)