Provides Java classpath and (compiled) Clojure namespace browsing.
Scans the classpath for all class files, and provides functions for
categorizing them. Classes are resolved on the start-up classpath only.
Calls to 'add-classpath', etc are not considered.

Class information is built as a list of maps of the following keys:
:name Java class or Clojure namespace name
:loc Classpath entry (directory or jar) on which the class is located
:file Path of the class file, relative to :loc

Vars in swank.util.class-browse