Apikey header name

[mutantsan]

Currently, we set the both headers - Authorization and X-CKAN-API-Key.

Some other plugins use the ckanapi for the RemoteCKAN client. Like the ckanext-syndicate, for example. And in the situation, when the remote portal is protected with the "Basic" HTTP authentication, we can't pass both basic auth authorization and ckan apikey.

Also, because we have this config option, the portal can use any header name for API token, and that's why we should make it configurable.

[wardi]

@mutantsan I've been able to use ckanapi with a site protected by basic auth by using -r https://username:password@the-site.com on the CLI.

You should be able to do the same with RemoteCKAN directly without any changes to the ckanapi code by passing the HTTP auth as part of the address parameter.