Update getCatalog() function to use base_url

[janette]

metasatore/src/Service.php is currently using a hard coded http://dkan from schema/collections/catalog, we want it to use the $base_url value instead

[kimwdavidson]

Use base URL scheme

[dafeder]

@janette I actualy don't see where this is happening? No hard-coded http://dkan I can find outside the tests, where we should probably change but they don't seem to be breaking atm. Can you confirm and either add back to the appropriate column of the Triage project or close? Thanks