Remove scripting language requirement from extension invocation interfaces

[kcoleman-marklogic]

We've determined that you do not need to provide the resource service extension implementation langauge when invoking the get/put/post/delete methods of a resource service extension.

I think that means that this interface change should come out, unless it's needed for managing the resources. In DatabaseClient, an overload of init was added to enable passing in the scripting language:

public <T extends ResourceManager> T init(String resourceName, T resourceManager, ExtensionsionMetadata.ScriptLanguage scriptLanguage);

The only place I see where we tell people to invoke init is in the wrapper class around extension usage, so I don't think that's the case. You'll know better, though.

[sravanr]

Updated the existing test in regression.