Review: JDK 8 CR for Support Integer overflow

[Roger Riggs]

Thanks for the review and comments:

The comments and suggestions are included in the updated webrev:
    http://cr.openjdk.java.net/~rriggs/6708398.1

  * Corrected error in multipleExact(long,long) with the special case
    Long.MIN_VALUE * -1.
  * Verified that retaining the optimization for small (2^31) arguments
    is worthwhile,
    not doing the divide saves about 1/2 on the execution time.
  * Removed the negateExact methods since they don't pull their weight
    in the API,
    simple tests for MIN_VALUE and MAX_VALUE can be done by the
    developer more efficiently.
  * Simplified the arguments to the ArithmeticExceptions to be simple
    strings since
    debugging this kind of exception requires the source code.
  * Expanded the comments in the implementation include descriptions and
    references to the Hackers Delight where they are used.
  * Updated the tests to include missing test cases

More comments, please

Thanks, Roger