Prepare Downhill Simplex for pull request

This is an implementation of so-called downhill simplex method
(https://en.wikipedia.org/wiki/Nelder%E2%80%93Mead_method)

Please, let me know if you have any comments, whoever you'd be.

modules/optim/src/debug.hpp

@@ -0,0 +1,18 @@
+namespace cv{namespace optim{
+#ifdef ALEX_DEBUG
+#define dprintf(x) printf x
+static void print_matrix(const Mat& x){
+    printf("\ttype:%d vs %d,\tsize: %d-on-%d\n",x.type(),CV_64FC1,x.rows,x.cols);
+    for(int i=0;i<x.rows;i++){
+        printf("\t[");
+        for(int j=0;j<x.cols;j++){
+            printf("%g, ",x.at<double>(i,j));
+        }
+        printf("]\n");
+    }
+}
+#else
+#define dprintf(x)
+#define print_matrix(x)
+#endif
+}}