go/parser: imaginary constants and ! may start an expression
go/parser: imaginary constants and ! may start an expression

Complete list of tokens that can start a top-level expression.

R=rsc
CC=golang-dev
http://codereview.appspot.com/5671074
abustany/go,abustany/go,abustany/go,abustany/go,abustany/go,abustany/go,abustany/go