GitLab

Adds features required for IFU integration or developed during the integration:

• Adds support for IFU files in gris_translate_headers
• Adds IFUFitsFile subcalss to GrisFitsfile
• Adds WCS generator for IFU data
• Added gris_parse_calib script to retrieve reduction settings from IDL scripts
• Switched WCS generation to structure using ABCs with more structured interface
• Removed too specific test for coordinates