install from repos automatically (PEP-508)

[1ucian0]

There is no need to consider the repo dependencies in a special way. After PEP-508, it is possible to set dependencies on github repos. This simplifies the installation guide.

[rsln-s]

@1ucian0 thank you for stopping by and submitting the pull requests! Just to let you know, a slightly improved version of the methods used in [1] is available here: https://github.com/rsln-s/variationaltoolkit

The specific method that implements multistart optimization using APOSMM is here:
https://github.com/rsln-s/variationaltoolkit/blob/1fcb864b1ec06c7c49ecd9afa30dc0ceeb02747b/variationaltoolkit/variationalquantumoptimizeraposmm.py#L76

If you have any issues getting variationaltoolkit or APOSMM to work, feel free to reach out to myself or @jmlarson1. Variationaltoolkit depends on an older qiskit, so care should be taken when using; there are some known issues with consistency between versions (e.g. qiskit-community/qiskit-aqua#1246)

[1] "Multistart Methods for Quantum Approximate Optimization" DOI: 10.1109/HPEC.2019.8916288