Favor functions over namespaces in ns op

This is of course subjective, but I'd call the current behavior broken. If a `str` namespace alias exists and I call `(doc str)` in the REPL, I get the docs for the `str` function. If I call `(source str)`, I get the source. The current implementation is incompatible with both.

From the perspective of a lookup symbol under cursor operation, aliases generally only appear as bare symbols after `:as` in a require, and in that particular case, it's easy enough to just lookup the original namespace (two words to the left) instead.