RFR(s): 8133977u1 add specification for serial form of immutable collections

[Stuart Marks]

Hi all,

Please review this updated webrev/specdiff. Changes since previous:

   - removal of mention of CollSer from the API specification
   - make CollSer's Object[] field transient, and handle its contents
     as custom serial data in readObject/writeObject
   - specification changes to reflect the above

Webrev:

     http://cr.openjdk.java.net/~smarks/reviews/8133977/webrev.1/

API specdiff:

 
http://cr.openjdk.java.net/~smarks/reviews/8133977/specdiff.1/api.specdiff/overview-summary.html

serialized-form.html diff:

 
http://cr.openjdk.java.net/~smarks/reviews/8133977/specdiff.1/serial.specdiff/specdiff-summary.html

Thanks,

s'marks