Docstring improvements.

Add checks for .pyo and .pyd.
Collapse docfunction, docmethod, docbuiltin into the one method docroutine.
Small formatting fixes.
Link the segments of a package path in the title.
Link to the source file only if it exists.
Allow modules (e.g. repr.py) to take precedence over built-ins (e.g. repr()).
Add interruptible synopsis scanner (so we can do searches in the background).
Make HTTP server quit.
Add small GUI for controlling the server and launching searches (like -k).
    (Tested on Win2k, Win98, and Linux.)