Remove SMWParamSource

I propose this alternate fix which gets rid of the deprecated legacy code altogether. The initial approach left the broken code broken (which I first fixed before realizing its better to kill it) and had a test bind to the patched legacy code (the test broke after I fixed the actual broken code).

Param resolving should be tested on a higher level (ie integration test) and not bind to any specifics of param processor. Maps is doing this. Perhaps SMW is as well somewhere, can't find it though.