fix web deployment classloader issue

Pass the builder's classloader to the LocalInstanceManager to find the
class using the ClassLoader in newInstance(String className).
Otherwise, if an AS7 service deploys a web app, it will fail with a
ClassNotFoundException since the jboss-web module will not be able to
find the class from the service's module.

The undertow org.jboss.as.undertow.Host#addWebDeployment does not suffer from this issue.