Contact variational integrators - native ocaml version

This is a collection of geometric solvers for initial value problems derived from contact Lagrangians. The provided solvers concern Lagrangians of the form $$
L(x, \dot{x}, z, t) = \frac12|\dot{x}|^2 + g1(x)g_2(z) + h(z) + f(t)x $$ For further information refer to _Vermeeren, Bravetti, Seri: Contact Variational Integrators (2019).