Rework edf2nx (add configuration file)

TODO

Requires tomoscan!77 (merged)

• use a configuration class instead of options provided directory
• allow several values for rotation angle key (see #101 (closed) )
• allow user to define unit of different field on the spec-edf as pixel size, sample / detector distance ... (see #100 (closed) )
• let user provide a different file prefix than the folder name and provide information contained in .info (see #98 (closed)) I guess those modifications will impact tomoscan
• let user define more angles options (see #97 (closed))
• improve handling of negative ScanRange (see #102 (closed) ).
• in order to let the user define a .info file and to avoid improving complexity of the code we will convert the .info contain into a dict and provide this one to the EDFTomoScan class
• add an application to generate an edf2nx configuration file
• update tutorial for edf2nx
• try to deduce field of view for edf as well
• move default distance , x/y/x translation to centimeter instead of meter. Make more sense.
• move tomoscan dependency to 0.9.0a

extra

• edf2nx: check input parameter is a folder. Otherwise raise an error
• close #102 (closed)
• close #101 (closed)
• close #100 (closed)
• close #99 (closed)
• close #98 (closed)
• close #97 (closed)