Fast ccd calibration

Adds the following functionality:

• option to define a different data path formating string
• FastCCD calibration output dark and relative gain corrected, common mode corrected, charge split classified and multiplicity patterns keys, gain map and bad pixel mask map
• subset option on load to selectively load some trains with 'by_index'
• option to select multiple ROIs from a source

merged

mentioned in commit 86388633