Add lots of new functions to key_name.py, including path/link_name processing.
Copy various link_name related regex patterns to key_name.py and use them.
Add error checking that raises a key_name.Error exception when name...()
functions are given empty arguments. Hard-code class names, since they match
what was typed into the module.class.__name__ to get the name anyway. This
eliminates dependencies on any modules by key_name.py.