Basic autogenerated definition for vectors.
Merged with upstream.
Throw BoundsError for invalid indices
Merge pull request #12 from jayschwa/bounds-error

Throw BoundsError for invalid indices
Macrofied higher-order functions for method definition.
Tweaked readme.
Retain vector type when negating

Fixes #13
Merge pull request #15 from jayschwa/negation

Retain vector type when negating
Addresses #14. Generalized the mapMethod function to work with binary operators.
Add some core tests for scalar operations