Merge pull request #17 from MaikKlein/master

Fixed operators like +=
Fix lifetime error
Untangle vec macros
Untangle mat macros
Remove dimensional HOFs
Move files into submodules
Add skeleton noise module
Add color module
Add octree and quadtree mods (not yet implemented)
Make point into standalone struct as opposed to a newtype struct
Fix color channel conversions
Rename Plane to Plane3 for consistency with other types
Re-export FrustumPoints from world module
Remove free standing color conversion functions
Relax type bounds
Use upper case identifiers for static constants
Reduce transmute ugliness
Merge some color modules
Simplify color::channel traits
Improve trait bounds