HPCC-10032 Add schema generator support for xpath('')

Add support for xpath('') to schema generation code in both hqlutil.cpp
and fileview2.

For child sets, datasets, and rows, xpath('') needs to generate
schemas where children of the field become direct children of the
current record. For simple types the parent complexType needs to
be marked as containing mixed content.  When xpath('') is nested
across multiple child levels, both mixed content and child elements
need to move up to the nearest parent with out xpath('').

Signed-off-by: Anthony Fishbeck <anthony.fishbeck@lexisnexis.com>
HPCC-9976 Add banner support to new ECL Watch

Fixes HPCC-9976

Signed-off-by: Gordon Smith <gordon.smith@lexisnexis.com>
HPCC-9322 Allow active name to be used with ecl-unpublish

Fix build break in previous commit

Signed-off-by: Richard Chapman <rchapman@hpccsystems.com>
Merge pull request #4974 from GordonSmith/HPCC-9976

HPCC-9976 Add banner support to new ECL Watch

Reviewed-By: Miguel Vazquez <miguel.vazquez@lexisnexis.com>
Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>
Merge pull request #5004 from richardkchapman/build-break

HPCC-9322 Allow active name to be used with ecl-unpublish

Reviewed-by: Gavin Halliday <ghalliday@hpccsystems.com>
Merge pull request #4983 from afishbeck/empty-xpath2

HPCC-10032 Add schema generator support for xpath('')

Reviewed-by: Gavin Halliday <ghalliday@hpccsystems.com>