HPCC-9197 Escape content when converting WsECL form to XML

Signed-off-by: Anthony Fishbeck <Anthony.Fishbeck@lexisnexis.com>
HPCC-9197 Leave generated xml tag open until attributes have been added

Signed-off-by: Anthony Fishbeck <Anthony.Fishbeck@lexisnexis.com>
Merge pull request #4312 from afishbeck/wseclFormXmlEscape9197

HPCC-9197 Escape content when converting WsECL form to XML

Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>