Consolidate this repo with Qibo

[marekgluza]

Hi all,

initially, part of this repo was intended for the qibo repo
qiboteam/qibo#1294

The PR draft has already test functions for e.g. group commutators.

Option 1.
Don't add any further DBQA to qibo:

• close 1294
• accept that DBI in qibo is a model only for dense matrices
• consider adding a dependancy on boostvqe for the gci model

Option 2.
Add GCI to Qibo because it has interesting circuit synthesis methods:

• Focus on general features such as
  • group commutators,
  • GCI,
  • evolution oracles.
• Keep here utils and additional documentation.

Option 3. First go with 1 and assign as onboarding project to someone to 2 port features to qibo and learn the PR process.

[marekgluza]

see qiboteam/qibo#1523

• qibo.models.dbi will be moved to a separate repo qiboteam/qibo-dbqa (similar to restructuring as QiboML)
• the evolution oracles and the GCI transpiler should be moved there
• the utilities for gradient descent etc should stay here