Item12360: Improve delimiter processing in LogDispatchContrib

Records are being written with leading and trailing spaces.

Newlines are encoded on write.  The records should be written as
presented.

Delimiter was extracted incorrectly for encoding, it wasn't working, but
was masked by the newline encoding.  Once the newline was removed, the
delimiter was empty and the regex failed.

eachEventSince should join records that are split by embedded newlines.

Add unit test for | encoding.

git-svn-id: http://svn.foswiki.org/trunk/LogDispatchContrib@16419 0b4bb1d4-4e5a-0410-9cc4-b2b747904278