Pinning the version of paket used should ensure that running of "paket
install" is reproducible ensuring our CI git diff check doesn't spuriously
fail.
* Move generators and assertions to helper library.
* Add example usage to bezier curve tests.
* Add FsCheck to OpenTK.Tests.Math via paket.
* Tweak fsharp msbuild settings for OpenTK.Tests.Generators.
Partly covered methods which converts between euler angles and quaternions.
Whats still missing here is applied rotation axis and rotation orientation (counter clockwise + right hand rule)