Update to slf4j 1.7.2 for now (handles multiple versions on the classpath better)

git-svn-id: https://svn.apache.org/repos/asf/webservices/wss4j/trunk@1454419 13f79535-47bb-0310-9956-ffa450edef68
Relax some checks a little to start working on getting CXF tests to pass "as is"

git-svn-id: https://svn.apache.org/repos/asf/webservices/wss4j/trunk@1454420 13f79535-47bb-0310-9956-ffa450edef68