Film negative processing: first usable version. Only supports bayer raw files, thumbnails don't work

Added performance improvements suggested by heckflosse. Lowered median sampling step from 7 to 5 since calculation is now much faster.

Added support for Fuji X-Trans raw files.

Applied SSE2 patch provided by @heckflosse, improves performance in main processing loop.

Moved film negative processing stuff in its own compilation unit.

Code cleanup: removed redundant omp directives.

Added check for dead pixels, going above threshold after inversion. ST_BAYER only for now.

Reverted leftover hack in cropwindow.cc

rtengine/procparams.h

@@ -1501,6 +1501,23 @@ struct RAWParams {
     static Glib::ustring getFlatFieldBlurTypeString(FlatFieldBlurType type);
 };
 
+
+/**
+  * Parameters of film negative
+  */
+struct FilmNegativeParams {
+    bool enabled;
+    double redExp;
+    double greenExp;
+    double blueExp;
+
+    FilmNegativeParams();
+
+    bool operator ==(const FilmNegativeParams& other) const;
+    bool operator !=(const FilmNegativeParams& other) const;
+};
+
+
 /**
   * This class holds all the processing parameters applied on the images
   */
@@ -1559,6 +1576,8 @@ public:
     ExifPairs               exif;            ///< List of modifications appplied on the exif tags of the input image
     IPTCPairs               iptc;            ///< The IPTC tags and values to be saved to the output image
 
+    FilmNegativeParams      filmNegative;    ///< Film negative parameters
+
     /**
       * The constructor only sets the hand-wired defaults.
       */