Don't name the crate "test"

[Manishearth]

Currently the actual crate library is named "test", which is confusing since there's a builtin crate of the same name.

Furthermore, the builtin crate is always loaded, so this conflicts with it and can cause "multiple matching crates found" errors at times. We should avoid that. Perhaps we can just call it tester?

[Manishearth]

Actually, the fact that this works at all really should be a crates.io bug.