[erlang-patches] DTrace patch, review draft #2

[Scott Lystig Fritchie]

Andreas, thanks for your work and advice.  I've included your
efile_drv.d converted script into
lib/dtrace/examples/efile_drv.systemtap.

OTP team, I've a new branch for review.  I know that the top-level
README.md changes aren't appropriate for the real OTP repo, but having
the diffs there is nice for people who visit my GitHub repo's page at
https://github.com/slfritchie/otp/tree/dtrace-review2.

Are there other things that might be preventing this branch from going
into the "pu" branch?

Changes since last push to GitHub (relative to commit 5828a4fb28,
which was the former `dtrace-review1` branch):
    * Rebased onto 14 Nov 2011's "master" branch
    * Recent changes to the async task queuing mechanism means that
      the async worker queue length is not available.  A bogus value
      of -1 is hard-coded until there's a good way to peek into the
      new queue structure and find the queue length.
    * Small fixes based on review comments by Mikael Pettersson,
      Andrew Thompson, and Andreas Schultz.

git clone git://github.com/slfritchie/otp.git dtrace-review2

https://github.com/slfritchie/otp/compare/dtrace-review2
https://github.com/slfritchie/otp/compare/dtrace-review2.patch

-Scott