Provide a new EmbeddedUtils.initializeForClientUse() method that can be used to
initialize the proper internal structures so that OpenDS code can be more
easily used for client-side applications that could benefit from the code but
don't want or need to be running in the same JVM as the server.

Also, update the DirectoryServer.bootstrapClient() method (which is what
EmbeddedUtils.initializeForClientUse() uses behind the scenes) can be called
multiple times on the same server instance without interfering with any
previous initialization that might have been done.  In short, it will ensure
that this initialization occurs no more than once during the life of the
DirectoryServer object instance.