RFR: JDK-8219002: Some comments and error messages refer to VMDisconnectException

[Gary Adams]

Trivial cleanup of a misspelled exception :
  VMDisconnectException
  VMDisconnectedException

  Webrev: http://cr.openjdk.java.net/~gadams/8219002/webrev.00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8219002