v0.4.0

• Add component casting APIs
  • num_cast — Numeric casts like with the as keyword
  • cast — Casts with the Into trait
  • try_cast — Casts with the TryInto trait
• Reduce type requirements for Vector::signum from Floats to all Signed types
• Add Vector::distance to calculate the Euclidean Distance between two points
• Add Vector::manhattan_distance to calculate the Manhattan Distance between points
• Add Vector::sum to sum the values of all components
• Add Vector::opposite to create a new vector with all components negated

Full Changelog: v0.3.0...v0.4.0