Resolved #30 to separate static & dynamic objects

The `add` and `add_multiple` functions in the CollisionDetector
interface now take an optional (default: false) `static` flag that
specifies whether the given object(s) is static or not. The
SpatialDictionary has also been updated to implement the knew interface.
Merge branch 'master' of https://github.com/NintenJoe/zol into Issue-30
Merge pull request #32 from NintenJoe/Issue-30

Resolved #30 to separate static & dynamic objects