HDFS Version 0.2

[evilk...@googlemail.com]

* The project has moved home. Since I had to change my ISP I needed
to rehouse HDFS. I decided to host it on google code and start a
related google group.
* http://code.google.com/p/hdfs/
* http://groups.google.com/group/hdfsharp

* Revised circuit design API. Where possible standard operators are
used and overloaded to allow integer and string arguments.

* Improved simulator which should fix the bugs in V0.1 and adds a few
extra optimisations. Completely redesigned API makes it much nicer to
work with.

* Basic constant propogation optimisations applied automatically as
circuits are built.

* Fixed point data type.

* A few new library circuits.

* HDCaml compatibility API.

* The beginnings of a synthesizer for Xilinx FPGAs. Although not
complete, to me it's quite remarkable what a few hundred lines of ML
can achieve. Main things still to do:
* Memory generation (distributed and block ram).
* Hard multiplier support.
* Fix buggy instantiation code.
* EDIF generator (trying to reverse engineer EDIF is about as much
fun as pulling out your own teeth...).

* Matlab Simulink model generator, kindly provided by John White.