8029904: Remove com.sun.security.auth.callback.DialogCallbackHandler

[Alan Bateman]

DialogCallbackHandler is the sample Swing based CallbackHandler in the 
JDK-specific API to JAAS. It's problematic for our modularity efforts 
and as folks may recall, we deprecated it in JDK 8 with a warning to say 
that it would be removed in a future release. It was also flagged in JEP 
162 as an impediment to the JDK modularization.

I'd like to get the second phase of this work (ie: remove it) into JDK 9 
early to give every opportunity for folks that folks that might have a 
dependency a chance find an alternative solution.

The webrev with the proposed changes is here:
   http://cr.openjdk.java.net/~alanb/8029904/webrev/

With these changes then all tests in the jdk_security jtreg group are 
passing. There will clearly be additional work to do beyond the code 
changes (like the JAAS guide) but that is for later.

-Alan