Review Request JDK-8192945: Need stable sort for MODULES entry in the release file

[mandy chung]

Updated webrev:
http://cr.openjdk.java.net/~mchung/jdk10/webrevs/8192945/webrev.01/

I kept the nodes as a Deque as it polls one node for traversal.   I 
fixed line 110-111 to use a Set.

thanks
Mandy