Make censor rules be case-insensitive

[HelenWDTK]

Firstname Surname, firstname surname, FIRSTNAME SURNAME and Firstname SURNAME should ideally be treated the same.

This was a problem that I came across as part of dealing with an RtO/RtE where the standard C&A rule missed some versions of the full name in plain text correspondence due to capitalisation. Users often capitalise their name in an inconsistent way.

[WilliamWDTK]

One could consider making this a tick-box, to (a) avoid potentially breaking previous censor rules, and (b) cover cases where you might still want it to be case sensitive.

[garethrees]

One could consider making this a tick-box

+1, or a select field for the useful regexp modes (multiline, case-insensitive, ignore whitespace).