expanded standard library

[JCBurnside]

basic implementation of

• std::vec::Vec
  • depends on externed items. #14
• std::boxed::Box
  • depends on externed items. #14
• std::seq
  • std::seq::map and std::seq::Map
  • std::seq::filter and std::seq::Filter
  • maybe more
• std::option::Option
  • depends on expanded pattern matching #15 and Discrimiated unions aka enums #13
• std::result::Result<T,E>
  • depends on expanded pattern matching #15 and Discrimiated unions aka enums #13

could maybe add more.