Refactor Slicesampler

- Fix: removed useless object.
Refactor Sampler initialisation

- Heavily refactored Sampler initialisation logic. Now easy to change data_gen later on. Changed theta_kappa/theta_gamma parameters as well, now default values nearly everywhere (which was the case anyway)
Added BIC computation in Sampler

- Added: BIC computation in Sampler directly. Tries to guess the number of parameters, check it when using it!
Load_experiment_data now has load_data_dualrecall()
Fix DataPBS for scalar output, tweak DataGen

- Fix: DataPBS did not handle scalar output properly. Now should be better.
- Fix: DataGen does not require stimuli_generation to be None when using stimuli_to_use
Heavily refactored FitExperiment

- Fix: FitExperiment changed completely. Now behaves as a ResultComputation (slightly). Give it a Sampler, and then it changes its DataGen automatically. Supports multiple datasets, assumes fixed T. Compute BIC score and/or Loglikelihood
- Added: SubmitPBS tries to reload and existing result_sync before submitting the job again. Allows for cool caching mechanism, completely robust to changes in parameters but still working well.
- Added: ResultComputation returning the name of the dataio filename. Useful when reloading the results saved during simulations, beyond just a result returned.
Reloader fitting experiment cool parameter re-submit

- Added: Super cool re-submitting of new jobs given extracted best parameters. Here used to get Memory curves and EM model fits for the best LL parameters found. Uses the new caching/reloading mechanism for minibatches.