Move Java info support from ASM to source parsing.

This moves Java `info` support essentially on par with Clojure. Specifically, we now have:

- `doc` and `jump` to source support for everything that has `.java` source code -- all classes, nested classes, interfaces, methods, and fields,
- actual `doc` text (not just URLs) for Java symbols,
- argument names (not just types) for Java arglists, and
- proper arglist arity for Clojure host interop (prepends `this` to instance method and field arglists).

It also removes the dependency on ASM in favor of the Java Compiler API. This does require `tools.jar`, but when that's not available, Java `info` falls back to simple reflection for basic symbol lookup.

I should note that Java symbol lookup can be "tuned" however we think makes sense. Right now qualified classes and static members are resolved universally, while unqualified classes and members are resolved in the current scope of `ns-imports`.