This ticket implements the basics of symplectic structures,
like Poisson brackets and Hamiltonian vector fields.

TODO (as follow-up tickets):

• Extract general coordinate stuff from EuclideanSpace
  to new class VectorSpace, and let SymplecticVectorSpace
  derive from VectorSpace

CC: @tscrim @nthiery @mjungmath @egourgoulhon @mkoeppe

Component: manifolds

Author: Tobias Diez

Branch: b78d8a2

Reviewer: Eric Gourgoulhon, Michael Jung, Matthias Koeppe, Travis Scrimshaw

Issue created by migration from https://trac.sagemath.org/ticket/30362