* Use new algos, remove FBPD

* Update mc demo to new algs.

* Fix bug overwriting b

* Move work_out_ajoint files

* Update sophiabeads 2d demo to new reader

* Update sophiabeads 3d demo

* Update to generic data path

* Demo read only required part of Nikon data

* Update nexus demo, still missing new reader.

* Nexus demo new loader. Data path still hardcoded.

* Add 3D ASTRA operator and nexus demo

* Add astra sophiabeads 3d demo

* 2D astra scaling working simple case, not sophiabeads

* Simplied bp scaling, now seems to work 2D incl sophiabeads

* MC correct astra fp and bp scaling

* Fixed also ASTRA BP scaling in 3D, works sophiabeads 3D

* Minor tidy up