HPCC-10590 Ignore ~ in subfile name from package

Can get xpath errors if the ~ is left in place.

Signed-off-by: Richard Chapman <rchapman@hpccsystems.com>
HPCC-10516 Roxie should ignore SubFile value="" in a package SuperFile

Package files may specify empty subfile names - this should not give Roxie
internal errors.

Signed-off-by: Richard Chapman <rchapman@hpccsystems.com>
Merge pull request #5258 from richardkchapman/roxie-empty-subfile

Roxie empty subfile

Reviewed-by: Gavin Halliday <ghalliday@hpccsystems.com>