- Extended the `Stack` models allowing for non-symmetric coupling between devices.
`Stack` current drivers can now be of any type and are adequately scaled.
- Custom definition of the `ScalarDriver` is now possible and documented.
- Fixed a bug in the `Stack` class which inverted the connection order of in-series connections.
- Exposed IDMI interaction to Layer and Junction classes.
- Added `getLayer` method to the `Junction` class and `getJunction` method to the `Stack` class that return a reference to the object.
- Fixed and expanded the `reservoir` module. Now, `GroupInteraction` can use any dipole interaction function, with 3 provided as default: `computeDipoleInteraction`, `computeDipoleInteractionNoumra` and `nullDipoleInteraction` (0 dipole tensor).