new_interrupt Provide a lighter-weight mechanism for interrupting.
Previously, when calling the non-"interruptible" versions of
the match and search methods, you would still see a penalty from
the interrupt checking. This change makes two modifications:
* A second mechanism for interrupting is added as a volatile
boolean on the matcher itself. You must have the matcher in
hand to set the flag. Setting the flag renders the matcher
"dead" and future search and match calls will raise again.
* The match and search methods call along a path that is only
interruptible by the volatile flag. The interruptible versions
also check the volatile for consistency.
The visible behavioral change here is that "match" and "search"
will not respond to Thread interrupt events anymore. If they need
to be interrupted, interrupt the matcher directly.
