Adding new tutorial to Plasmo

[KiernanJ]

New tutorial implementation of multi-horizon MPC to Plasmo. Super simple example for beginners in optimization, JuMP, and Plasmo.

[jalving]

Hi @KiernanJ, thanks for your contribution! We had some issues with an old workflow. Can you try merging the latest main into your PR? It should re-trigger the checks.

[dlcole3]

Thank you for adding the MHMPC function! One last request on this: can put these blocks into their own function calls just to make the code a little easier to copy over for a potential user? Something like what is in the optimal control of a quadcopter example: https://plasmo-dev.github.io/Plasmo.jl/dev/tutorials/quadcopter/

I think you can do something like:

function add_horizon_subgraphs()
    # All of the subgraphs
    graph_SG1 = OptiGraph()
    graph_SG2 = OptiGraph()
    graph_SG3 = OptiGraph()
    graph_SG4 = OptiGraph()
    graph_SG5 = OptiGraph()

    subgraphs_all = [graph_SG1, graph_SG2, graph_SG3, graph_SG4, graph_SG5]

    # Initialize all nodes for subgraphs
    @optinode(graph_SG1, nodes1[1:N_i[1]])
    @optinode(graph_SG2, nodes2[1:N_i[2]])
    @optinode(graph_SG3, nodes3[1:N_i[3]])
    @optinode(graph_SG4, nodes4[1:N_i[4]])
    @optinode(graph_SG5, nodes5[1:N_i[5]])

    

    nodes_all = [graph_SG1[:nodes1], graph_SG2[:nodes2], graph_SG3[:nodes3], graph_SG4[:nodes4], graph_SG5[:nodes5]]
    return subgraphs_all, nodes_all
end

Then you can do something like this farther down

function MHMPC
    graph = OptiGraph()
    subgraphs_all, nodes_all = add_horizon_subgraphs(graph)
    ...
end

[dlcole3]

Maybe at the end of this last code snippet, add the code to call the run_sim function. Just something like:

x_sim, u_sim = run_sim()

[dlcole3]

@jalving any objections if we merge this? @KiernanJ updated the code and merged the previous main into this PR.

[jalving]

this looks good to me!