Julia 0.3 release blog post

Seems like a good idea to have this on the web too? Elliot's text from the email.

@staticfloat @StefanKarpinski
Given that this blog post will probably be posted on HackerNews/Reddit/Twitter/etc without much context, it may be nice to add a bit here to pre-empt the question of "what is Julia?"  I know you can simply click on the giant Julia logo to get the information on the main page, but I think it's worth doing a little advertising for new users right up front.

What do you think about putting a snippet from the home page as the second sentence here? "Julia is a high-level, high-performance dynamic programming language for technical computing, with syntax that is familiar to users of other technical computing environments."