Targetting 3.0.0

With so many fatures baked into this release, I think now is a good time
to bump the major version number.

Some major things off the top of my head:

* Hack - hacklang.org
* Removing libevent server
* Switching from hdf to ini
* mysqli
* Moved many functions to \HH namespace
* error message format change
* ... many more once I write the blog post