Remove serpent-go

[tgerring]

script_windows.go always returns nil, nil instead of calling to serpent-go

[maran]

I couldn't get serpent-go to build on windows previously, perhaps that explains nil, nil returns

[tgerring]

@obscuren Is this something we should attempt to improve or remove in light of Solidity as the primary language?

[obscuren]

Indeed removed. Compilation / deployment should be handled in another client (e.g. Mix)