Fix pix_opencv build on Archlinux (only one failing is now `pix_opencv_blobtrack`).

fix_build_archlinux.diff

Index: Makefile
===================================================================
--- Makefile	(revision 17144)
+++ Makefile	(working copy)
@@ -6,7 +6,7 @@
 # add your .cc source files, one object per file, to the SOURCES
 # variable, help files will be included automatically, and for GUI
 # objects, the matching .tcl file too
-SOURCES = pix_opencv_edge.cc pix_opencv_laplace.cc pix_opencv_morphology.cc pix_opencv_distrans.cc pix_opencv_motempl.cc pix_opencv_haarcascade.cc pix_opencv_contours_boundingrect.cc pix_opencv_bgsubstract.cc pix_opencv_contours_convexity.cc pix_opencv_dft.cc pix_opencv_lk.cc pix_opencv_hist_compare.cc pix_opencv_knear.cc pix_opencv_threshold.cc pix_opencv_floodfill.cc pix_opencv_athreshold.cc pix_opencv_bgstats.cc pix_opencv_camshift.cc pix_opencv_hu_compare.cc pix_opencv_pgh_compare.cc pix_opencv_hough_circles.cc pix_opencv_hough_lines.cc pix_opencv_hu_moments.cc pix_opencv_contours_convexhull.cc pix_opencv_colorfilt.cc pix_opencv_of_bm.cc pix_opencv_of_hs.cc pix_opencv_of_lk.cc pix_opencv_calibration.cc pix_opencv_warpperspective.cc pix_opencv_findchessboardcorners.cc pix_opencv_blobtrack.cc pix_opencv_contours.cc pix_opencv_matchshape.cc
+SOURCES = pix_opencv_edge.cc pix_opencv_laplace.cc pix_opencv_morphology.cc pix_opencv_distrans.cc pix_opencv_motempl.cc pix_opencv_haarcascade.cc pix_opencv_contours_boundingrect.cc pix_opencv_bgsubstract.cc pix_opencv_contours_convexity.cc pix_opencv_dft.cc pix_opencv_lk.cc pix_opencv_hist_compare.cc pix_opencv_knear.cc pix_opencv_threshold.cc pix_opencv_floodfill.cc pix_opencv_athreshold.cc pix_opencv_bgstats.cc pix_opencv_camshift.cc pix_opencv_hu_compare.cc pix_opencv_pgh_compare.cc pix_opencv_hough_circles.cc pix_opencv_hough_lines.cc pix_opencv_hu_moments.cc pix_opencv_contours_convexhull.cc pix_opencv_colorfilt.cc pix_opencv_of_bm.cc pix_opencv_of_hs.cc pix_opencv_of_lk.cc pix_opencv_calibration.cc pix_opencv_warpperspective.cc pix_opencv_findchessboardcorners.cc pix_opencv_contours.cc pix_opencv_matchshape.cc pix_opencv_blobtrack.cc
 
 # list all pd objects (i.e. myobject.pd) files here, and their helpfiles will
 # be included automatically
Index: pix_opencv_lk.cc
===================================================================
--- pix_opencv_lk.cc	(revision 17144)
+++ pix_opencv_lk.cc	(working copy)
@@ -17,6 +17,7 @@
 
 #include "pix_opencv_lk.h"
 #include <stdio.h>
+#include "opencv2/legacy/legacy.hpp"
 
 CPPEXTERN_NEW(pix_opencv_lk)
 
Index: pix_opencv_of_bm.cc
===================================================================
--- pix_opencv_of_bm.cc	(revision 17144)
+++ pix_opencv_of_bm.cc	(working copy)
@@ -17,6 +17,7 @@
 
 #include "pix_opencv_of_bm.h"
 #include <stdio.h>
+#include "opencv2/legacy/legacy.hpp"
 
 CPPEXTERN_NEW(pix_opencv_of_bm)
 
Index: pix_opencv_of_hs.cc
===================================================================
--- pix_opencv_of_hs.cc	(revision 17144)
+++ pix_opencv_of_hs.cc	(working copy)
@@ -17,6 +17,7 @@
 
 #include "pix_opencv_of_hs.h"
 #include <stdio.h>
+#include "opencv2/legacy/legacy.hpp"
 
 CPPEXTERN_NEW(pix_opencv_of_hs)
 
Index: pix_opencv_of_lk.cc
===================================================================
--- pix_opencv_of_lk.cc	(revision 17144)
+++ pix_opencv_of_lk.cc	(working copy)
@@ -17,6 +17,7 @@
 
 #include "pix_opencv_of_lk.h"
 #include <stdio.h>
+#include "opencv2/legacy/legacy.hpp"
 
 CPPEXTERN_NEW(pix_opencv_of_lk)