[General] Release 2.0

[ocots]

Before we release the new 2.0 version of OptimalControl, we need to complete some things.

• Make a new stable release of CTBase
• Make a new stable release of CTModels
• Remove prefixes when display the description of a parameter (with a registry), see the describe function.
• Make a new stable release of CTSolvers
• Finalise and merge feat: support optimal control problems with zero-dimensional control CTParser.jl#246
• Make a new stable release of CTParser
• Make a new stable release of CTDirect which will include 0 dim control support
• Prefix all CTFlows functions in https://github.com/control-toolbox/CTFlows.jl/blob/c75e770fe9057b5469de077ea24f079b9ce635d2/src/differential_geometry.jl#L612-L675 with CTFlows
• Do not reexport types from CTFlows but only CTFlows:

  OptimalControl.jl/src/imports/ctflows.jl

  Line 4 in 0f84eec

  @reexport import CTFlows: Hamiltonian, HamiltonianLift, HamiltonianVectorField

• Add tests in OptimalControl for the indirect method: flow, resolution but also some Lie computations
• Finalise and merge https://github.com/control-toolbox/OptimalControl.jl/pull/718/changes
• Add a word about 0 dim control support in the documentation
• Add a word about Lie computations in the documentation

Documentation

• replace $\partial(q)$ by $\dot{q}$ (same for $v$):

  OptimalControl.jl/docs/src/example-double-integrator-energy.md

  Lines 52 to 53 in 0f84eec

  	∂(q)(t) == v(t)
  	∂(v)(t) == u(t)

• show the initial guess with a max_iter = 0.
• in the descriptions of the parameters, we have for instance the prefix CTSolvers.Modelers. This should be removed.