Statistics library

[dsimcha]

Now that I've figured out how the heck to use SVN, it's up on scrapple.
Everything basically has unittests and has been dogfooded by me, but if there are
any bugs I missed, please file.  I'm actually kind of surprised at the level of
interest in this project.

http://dsource.org/projects/scrapple/browser/trunk/statistics

Just a reminder:  The current version makes pretty heavy use of D2 features, so it
is completely incompatible with D1.  D1 compatibility was not even a consideration
in the design of anything.  I have no intention of backporting to D1, since D2 is
getting pretty close to ready anyhow.

Also, I'm not a lawyer, but the intent of the license I put in the header of the
files is to be very permissive to allow integration into Phobos and Tango of
whatever functionality Andrei and Don see fit.  If you see a problem with the way
I have worded the license, let me know and I'll change it.