HPCC-11489 Add simple crosssite Roxie call

Add "CallURL" method to WsEcl.js

Fixes HPCC-11489

Signed-off-by: Gordon Smith <gordon.smith@lexisnexis.com>
Merge pull request #5938 from GordonSmith/HPCC-11489

HPCC-11489 Add simple crosssite Roxie call

Reviewed-By: Miguel Vazquez <miguel.vazquez@lexisnexis.com>
Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>