Cleaned out unused imports
package io.nats.client.impl;
import java.security.SecureRandom;
-import java.security.cert.Certificate;
-import java.security.cert.CertificateException;
import java.security.cert.X509Certificate;
-import java.util.Set;
import javax.net.ssl.SSLContext;
import javax.net.ssl.TrustManager;
