title: APNS certificate expiry date error with MobileFirst Platform 7.0
body: <p>When deploying an APNS certificate in a .wlapp file in MFP 7.0, I'm seeing a null-pointer exception when it validates the end-date, even though it has one. ( <code>openssl pkcs12 -in apns-certificate-sandbox.p12 | openssl x509  -noout -enddate</code> returns a valid date in the future).
    It seems others have made this work, so I'm guessing it must be something I am doing wrong...has anyone else resolved similar issues with valid Apple Push Notification Service certs failing to be deployed on MFP
  Relevant lines from the log:</p>
  
  <pre>
  947: "com.ibm.worklight.admin.services.ApplicationService E FWLSE3000E: A server error was detected.",
  "948: com.ibm.worklight.admin.common.util.exceptions.ValidationException: FWLSE3119E: APNS certificate validation failed. See additional messages for details.",
  "949: at com.ibm.worklight.admin.util.PushEnvironmentUtil.validateApnsConfiguration(PushEnvironmentUtil.java:232)",
  "950: at com.ibm.worklight.admin.util.PushEnvironmentUtil.validatePushConfiguration(PushEnvironmentUtil.java:220)",
      [ ... lots more trace here .. ]
  "1030: Caused by: java.lang.NullPointerException",
  "1031:  at java.io.ByteArrayInputStream.(ByteArrayInputStream.java:117)",
  "1032:  at com.ibm.worklight.admin.util.PushEnvironmentUtil.getCertificateExpiryDate(PushEnvironmentUtil.java:362)",
  "1033:  at com.ibm.worklight.admin.util.PushEnvironmentUtil.validateApnsConfiguration(PushEnvironmentUtil.java:230)",
  </pre>