Clean up the DOMException code and move it to dom-aspects.

git-svn-id: https://svn.apache.org/repos/asf/webservices/axiom/trunk@1611812 13f79535-47bb-0310-9956-ffa450edef68
Unify the detach code.

git-svn-id: https://svn.apache.org/repos/asf/webservices/axiom/trunk@1611822 13f79535-47bb-0310-9956-ffa450edef68