v0.8.0

ConstrainedDynamics v0.8.0

Diff since v0.7.4

Merged pull requests:

• Higher order integration (#49) (@janbruedigam)
• Update ci to Julia 1.6 (#56) (@janbruedigam)
• Small factorization update (#57) (@janbruedigam)
• Fix input derivatives (#59) (@janbruedigam)
• Fix setvel mincoords (#64) (@janbruedigam)
• Rename UnitQuaternion to QuatRotation and fixes (#65) (@janbruedigam)