Nifty6tonifty7

See merge request !526

Fix dtype handling

See merge request !525

Wrap all scripts in functions

See merge request !524

This is best practise in python scripts in order no to clutter the global
namespace.

Fixups regarding constant minimization, nanisinf for EnergyAdapter

See merge request !523

Make Jacobian test distinguish C and R differentiability

Closes #304

See merge request !522

__repr__ methods for _FunctionApplier, _Amplitude and _LognormalMomentMatching

See merge request !520

Provide some MPI utilities in utilities.py

See merge request !519

Support complex data in `VariableCovarianceGaussianEnergy` and use simplify for constant input for KL and `EnergyAdapter`

See merge request !509

Simpler way of MPI summation

See merge request !512

Fix badges for nifty7

See merge request !514

Remove badges here

See merge request !513

Cleanupdemo

See merge request !516

Tiny cleanup in Linearization.prepend_jac

See merge request !515