HPCC-11016 Fix fileview output of EBCIDIC strings

Also fix regression of XML schema for XML output.

Signed-off-by: Anthony Fishbeck <anthony.fishbeck@lexisnexis.com>
Merge pull request #5603 from afishbeck/jsonResultBadChars

HPCC-11016 Fix fileview output of EBCIDIC strings

Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>