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Added the definition of a Region Of Interest (ROI) (iRA0, iRA1, iDEC0, iDEC1, iFREQ0, iFREQ1) in a cube. The interactions with the bottom left window ( box ) define iRA0, iRA1, iDEC0 and iDEC1, the interactions with the bottom right window ( box ) define iFREQ0 and iFREQ1. The six values are sent via a link to the ThreedJS tool along with the FITS file relative path

Generalized the systematic use of relFITSFilePath as the variable or key name to specify the path to a FITS file relative to its root directory on the server ( cf. env var YAFITSS_FITSDIR )

Fixed the most stupid typo which was preventing the spectrum from being drawn with the desired orientation

Adapted the code so that it takes into account the configuration environment variables and can be easly deployed