Added packages to GlobalEnvironment
Merge branch 'interpreter' of https://github.com/kobreu/compiler into interpreter
Merge branch 'interpreter' of https://github.com/kobreu/compiler into interpreter
Merge branch 'interpreter' of https://github.com/kobreu/compiler into interpreter
Merge branch 'interpreter' of https://github.com/kobreu/compiler into interpreter
Added require method
Merge branch 'interpreter' of https://github.com/kobreu/compiler into interpreter