sinograms.geometry module

[jadball]

Handles things like:

• iy index to/from dty value (accounting for y0 and ystep)
• recon array indices to/from real space (x,y) values (accounting for y0, ystep and padding)
• (dty,omega) values to/from real space (x,y) values (via fitting sine waves)
• test/debug whether sinograms/roi_iradon.py:recon_cens matches the same geometry

Also needs unit tests

[jonwright]

There is also a tweak needed somewhere near transform.py for the sample-detector distance changes due to thickness.

[jonwright]

• test/debug whether sinograms/roi_iradon.py:recon_cens matches the same geometry