Sqlparser

Added SQL parser based on vitess's SQL parser.

Does vitess also generate other source files but not check them in? Just
seems like we should be consistent. Hard to argue with line counts though.

On Friday, September 19, 2014, Peter Mattis <notifications@github.com>
wrote:

> In sql/parser/sql.go:
>
> > @@ -0,0 +1,1787 @@
> > +//line sql.y:6
>
> Vitess has it checked in. I was just following their lead. And it bumps up
> my line count. Do you feel strongly about it?
>
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