* Add From impls to convert between UnitQuaterion/UnitComplex and Rotation2/3
* Add rotation extraction from a Matrix2 or Matrix3.
* Add fast Taylor renormalization for Unit.
Fix 376.
* Add renormalization for Rotation3.
Renormalization for Rotation2 requires Complex to implement VectorSpace which will be fixed only on alga v0.9
* Update Changelog.