Gridcal

- General bug fix
- Improved results saving and loading
- Added more OPF testing
- Improved ACOPF
- Improved CGMES interoperability

What's Changed
* Generalised Powerflow for ACDC, Controls by leeraiyan in https://github.com/SanPen/GridCal/pull/273
* Bump idna from 2.10 to 3.7 by dependabot in https://github.com/SanPen/GridCal/pull/276

New Contributors
* leeraiyan made their first contribution in https://github.com/SanPen/GridCal/pull/273

**Full Changelog**: https://github.com/SanPen/GridCal/compare/5.1.0...v5.1.7

This release comes packed with functionality and bug fixes, but above all, a new file format.

- Sparse profiles; Profiles in objects are not numpy arrays anymore. Instead they are objects that can host either sparse or dense profiles depending on the nature of the data stored. This lowers the memory requirements for large models.
- New file format based on Json instead of CSV. This allows more flexibility when defining complex objects-within-objects like a tap changer or sparse profiles. GridCal is guaranteed to keep old-files compatibility.
- ACOPF with Generation dispatch, HVDC line dispatch and transformer tap module and angle dispatch.
- Better graphics: Buses and branches now display information. The internals have been refactored to simplify and debug.
- General UI overhaul: Simplified working of the buttons, new context menus and bug fixes.
- Best in class linear analysis, now with SRAP option to avoid N-1.
- Many more tests have been produced.

- Added fluid transport problem
- Overall bug fix
- OR Models fix themselves when infeasible

- Massive refactor to allow multiple bus-branch diagrams and maps.

- The great split: Now there are two packages: `GridCal` which delas with the graphical user interface and `GridCalEngine` that provides all the engine functionality without Qt dependencies.

- MIP auto-healing: OPF simuations are always feasible by properly relaxing infeasible ones.

- Added cutting edge investments evaluation. This will be evolved in future releases.

- API naming unification

- Overall refactoring and bug fixing

- Added special contingency, Contingency Groups, Investment and Investment group objects
- Added contingency planner GUI
- Added proper QT-based maps
- Refactored Time series to accurately reflect any change in the time series
- Refactored the contingency analysis to use contingency groups and reflect any grid change
- Overall bug fixes


- Improvements to CIM import
- Improvements to PSSe .raw imports
- Improvements to Alliander PGM support
- Improvements to inter-area net transfer capacity calculation
- Implemented new json file filters (.ejson3)
- Added profile sparsity in .ejson3 export.
- Added Newton Power Analytics support
- Better coordinates from latitude/longitude conversion by removing the often, massive offset.
- Many small bugs resolved.