For equality string matches other engines ignore trailing whitespace
(this does not apply to LIKE matches). So we should do the same. This
patch trims whitespace for MIN/MAX extent elimination checks, fixed
width columns and dictionary columns during equality matches against
constants (SELECT * FROM t1 WHERE b = 'ABC').
pDictionaryScan won't work for BLOB/TEXT since it requires searching the
data file and rebuilding the token from matches. The tokens can't be
rebuild correctly due the bits in the token used for block counts. This
patch forces the use of pDictionaryStep instead for WHERE conditions.
In addition this patch adds support for TEXT/BLOB in various parts of
the job step processing. This fixes things like error 202 during an
UPDATE with a join condition on TEXT/BLOB columns.
