geometry/rotations

Adds utility methods for quaternions / rotations. Moves existing code from core/math to the geometry module. Furthermore, the namespace of the floats module was removed - we tend to create too many namespaces imho, which is not very "user-friendly".

New Features

• [geometry]: Added quaternion and rotation related methods to geometry/rotations
• [core]: floats.hpp now provides a new method isZero() for convenient and safe comparison to zero

Bug Fixes

• [geometry]: quaternionNaturalLogarithm now returns a correct result for all quadrants and uses a taylor series approximation for small angle

Non-Breaking Changes

• [doxygen]: Minor documentation improvements.

Breaking Changes

• [core]:
  • Moved existing quaternion-related methods to geometry/rotations.hpp
  • The methods in floats.hpp are no longer in a separate namespace. Furthermore, floats.hpp is no longer required by math.hpp