const not implemented

[afbarnard]

Importing modules that define constants with "const" causes a panic:
panic: const not implemented

go version go1.0.3 on linux_amd64

go-eval version: commit 7de4c49

I am very excited to have a Go interpreter in which to try things out! (Contrary to some conversations on golang-nuts, I see the primary value of an interpreter as an interactive computing environment a la IPython.) I eagerly await future versions with more features.