Handle multiple imports environments

[CryZe]

I'm not actually sure how they are being handled at the moment, but if they actually all generate proper methods on the Imports trait, then we don't actually handle any name collisions properly as far as I can tell. This needs to be resolved by either prefixing the function names by the environment name or splitting up the trait. Additionally prefixing is probably not necessary if there's only a single environment and probably not when there's no collisions in the first place (although the latter sounds like an option you might want to change).