Fix missing format when writing Algorithm-based objects

Added a writeFormat() method to Algorithm which must be called by the
write() method of derived classes.

modules/photo/src/align.cpp

@@ -184,6 +184,7 @@ public:
 
     void write(FileStorage& fs) const
     {
+        writeFormat(fs);
         fs << "name" << name
            << "max_bits" << max_bits
            << "exclude_range" << exclude_range

modules/photo/src/calibrate.cpp

@@ -141,6 +141,7 @@ public:
 
     void write(FileStorage& fs) const
     {
+        writeFormat(fs);
         fs << "name" << name
            << "samples" << samples
            << "lambda" << lambda
@@ -250,6 +251,7 @@ public:
 
     void write(FileStorage& fs) const
     {
+        writeFormat(fs);
         fs << "name" << name
            << "max_iter" << max_iter
            << "threshold" << threshold;

modules/photo/src/merge.cpp

@@ -265,6 +265,7 @@ public:
 
     void write(FileStorage& fs) const
     {
+        writeFormat(fs);
         fs << "name" << name
            << "contrast_weight" << wcon
            << "saturation_weight" << wsat

modules/photo/src/tonemap.cpp

@@ -83,6 +83,7 @@ public:
 
     void write(FileStorage& fs) const
     {
+        writeFormat(fs);
         fs << "name" << name
            << "gamma" << gamma;
     }
@@ -161,6 +162,7 @@ public:
 
     void write(FileStorage& fs) const
     {
+        writeFormat(fs);
         fs << "name" << name
            << "gamma" << gamma
            << "bias" << bias
@@ -242,6 +244,7 @@ public:
 
     void write(FileStorage& fs) const
     {
+        writeFormat(fs);
         fs << "name" << name
            << "gamma" << gamma
            << "contrast" << contrast
@@ -339,6 +342,7 @@ public:
 
     void write(FileStorage& fs) const
     {
+        writeFormat(fs);
         fs << "name" << name
            << "gamma" << gamma
            << "intensity" << intensity
@@ -446,6 +450,7 @@ public:
 
     void write(FileStorage& fs) const
     {
+        writeFormat(fs);
         fs << "name" << name
            << "gamma" << gamma
            << "scale" << scale