Update Readme.txt
Fix a bug in funcion bg.threshold
Add 1d coords update docs
Add ipython notebooks for 1d coordinate updates
more cgls 1d coord updates
removed duplicate
Add coords_update_1d for 1d sample 2d probe
Merge branch '1d_cgls_coords' of https://github.com/andyofmelbourne/Ptychography into 1d_cgls_coords