Remove old OSGi 3 dependency, use only latest org.osgi.core R6

git-svn-id: https://svn.apache.org/repos/asf/directory/shared/trunk@1646565 13f79535-47bb-0310-9956-ffa450edef68
Fix another race condition when starting ldap-net-mina bundle within an OSGi runtime. Don't use static lookup for LdapApiService but do lookup from OSGi. Use ServiceTracker to decouple bundle start from service lookup.

git-svn-id: https://svn.apache.org/repos/asf/directory/shared/trunk@1646566 13f79535-47bb-0310-9956-ffa450edef68