OAK-696 : Support usage of JAAS based authentication with Repository in OSGi

Moving the org.apache.felix.jaas.boot package to DynamicImport as its only required when Felix JAAS Support Bundle is present

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1458645 13f79535-47bb-0310-9956-ffa450edef68