HPCC-9812 Let the user add "remote" files for spraying

Fixes HPCC-9812

Signed-off-by: Gordon Smith <gordon.smith@lexisnexis.com>

Conflicts:
	esp/src/eclwatch/LZBrowseWidget.js
Merge pull request #5826 from GordonSmith/HPCC-9812

HPCC-9812 Let the user add "remote" files for spraying

Reviewed-By: Miguel Vazquez <miguel.vazquez@lexisnexis.com>
Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>