HPCC-9892 Remove need for LOADXML for template language

Code to so already implemented however, it was still being reported as an error
and thus finaly aborting compilation. Also removed dummy uses of LOADXML within
ecl/regress.

Signed-off-by: jamienoss <james.noss@lexisnexis.com>
Merge pull request #5549 from jamienoss/issue9892-remove-need-for-loadxml

HPCC-9892 Remove need for LOADXML for template language

Reviewed-By: Gavin Halliday <gavin.halliday@lexisnexis.com>
Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>