Added some preliminary test cases for xmerlrpc parser.
Heavily rewritten error handling in XML parser.
Renamed tests.
Reorganized way of error reporting from XML builder functions.
Changed the way xmerlrpc returns value from remote calls.
Rewritten xmerlrpc:call/3 to return {error,Reason} instead of dying.

Now it's a bunch of nested cases. Not very pretty, but well, it does its job.
Version bump.
xmerlrpc:call() now returns {exception,What} on remote exception.

{error,Reason} is reserved to protocol errors.