recolor_image function can now be used with custom colors

doc/function/flip_horizontal.txt

 Function: flip_horizontal
 
+DOC_MSE_VERSION: since 0.3.9
+
 --Usage--
 > flip_horizontal(input: image)
 

doc/function/flip_vertical.txt

 Function: flip_vertical
 
+DOC_MSE_VERSION: since 0.3.9
+
 --Usage--
 > flip_vertical(input: image)
 

doc/function/invert_image.txt

 Function: invert_image
 
+DOC_MSE_VERSION: since 0.3.9
+
 --Usage--
 > invert_image(input: image)
 

doc/function/recolor_image.txt

 Function: recolor_image
 
+DOC_MSE_VERSION: since 0.3.9
+
 --Usage--
 > recolor_image(input: image, color: color)
+> recolor_image(input: image, red: color, green: color, blue: color, white: color)
 
 Re-color an image:
  * Red is replaced by the color
@@ -13,14 +16,26 @@ Re-color an image:
 This function is mostly intended to make symbols in a symbol font wich can match the text color.
 
 
-
 --Parameters--
 ! Parameter	Type			Description
 | @input@	[[type:image]]		Image to recolor.
 | @color@	[[type:color]]		Color by which to replace red.
 
+Or
+! Parameter	Type			Description
+| @input@	[[type:image]]		Image to recolor.
+| @red@		[[type:color]]		Color by which to replace red.
+| @green@	[[type:color]]		Color by which to replace green.
+| @blue@	[[type:color]]		Color by which to replace blue.
+| @white@	[[type:color]]		Color by which to replace white.
+
+
 --Examples--
-> recolor_image("symbol1.png", color: rgb(180,0,0))  ==  [[Image]]
+> recolor_image("symbol1.png", color: rgb(180,0,0)) == [[Image]]
 >>> recolor_image(<img src="symbol1.png" alt='"symbol1.png"' style="border:1px solid black;vertical-align:middle;margin:1px;" />, color: rgb(180,0,0)) == <img src="symbol1_red.png" alt='"symbol1_red.png"' style="border:1px solid black;vertical-align:middle;margin:1px;" />
-> recolor_image("symbol1.png", color: rgb(100,255,0))  ==  [[Image]]
+> recolor_image("symbol1.png", color: rgb(100,255,0)) == [[Image]]
 >>> recolor_image(<img src="symbol1.png" alt='"symbol1.png"' style="border:1px solid black;vertical-align:middle;margin:1px;" />, color: rgb(100,255,0)) == <img src="symbol1_green.png" alt='"symbol1_green.png"' style="border:1px solid black;vertical-align:middle;margin:1px;" />
+
+Custom choices for green, blue and white are also possible:
+>>> recolor_image(<img src="symbol1.png" alt='"symbol1.png"' style="border:1px solid black;vertical-align:middle;margin:1px;" />, red:rgb(0,170,0), green:rgb(200,0,255), blue:rgb(128,0,0), white:rgb(220,255,0))
+>>>    ==  <img src="symbol1_recolor_custom.png" alt='"symbol1_recolor_custom.png"' style="border:1px solid black;vertical-align:middle;margin:1px;" />

doc/function/rotate.txt

-Function: flip_vertical
+Function: rotate
+
+DOC_MSE_VERSION: since 0.3.9
 
 --Usage--
 > rotate(input: image, angle: some_number)

doc/function/saturate.txt

 Function: saturate
 
+DOC_MSE_VERSION: since 0.3.9
+
 --Usage--
 > saturate(input: image, amount: saturation amount)
 

src/gfx/generated_image.cpp

@@ -221,6 +221,20 @@ bool RecolorImage::operator == (const GeneratedImage& that) const {
 	             && color == that2->color;
 }
 
+Image RecolorImage2::generate(const Options& opt) const {
+	Image img = image->generate(opt);
+	recolor(img, red,green,blue,white);
+	return img;
+}
+bool RecolorImage2::operator == (const GeneratedImage& that) const {
+	const RecolorImage2* that2 = dynamic_cast<const RecolorImage2*>(&that);
+	return that2 && *image == *that2->image
+	             && red == that2->red
+	             && green == that2->green
+	             && blue == that2->blue
+	             && white == that2->white;
+}
+
 // ----------------------------------------------------------------------------- : FlipImage
 
 Image FlipImageHorizontal::generate(const Options& opt) const {

src/gfx/generated_image.hpp

@@ -227,6 +227,17 @@ class RecolorImage : public SimpleFilterImage {
   private:
 	Color color;
 };
+/// Recolor an image, with custom colors
+class RecolorImage2 : public SimpleFilterImage {
+  public:
+	inline RecolorImage2(const GeneratedImageP& image, Color red, Color green, Color blue, Color white)
+		: SimpleFilterImage(image), red(red), green(green), blue(blue), white(white)
+	{}
+	virtual Image generate(const Options& opt) const;
+	virtual bool operator == (const GeneratedImage& that) const;
+  private:
+	Color red,green,blue,white;
+};
 
 // ----------------------------------------------------------------------------- : FlipImage
 

src/script/functions/image.cpp

@@ -93,8 +93,15 @@ SCRIPT_FUNCTION(invert_image) {
 
 SCRIPT_FUNCTION(recolor_image) {
 	SCRIPT_PARAM_C(GeneratedImageP, input);
-	SCRIPT_PARAM(Color, color);
-	return intrusive(new RecolorImage(input,color));
+	SCRIPT_OPTIONAL_PARAM(Color, red) {
+		SCRIPT_PARAM(Color, green);
+		SCRIPT_PARAM(Color, blue);
+		SCRIPT_PARAM_DEFAULT(Color, white, *wxWHITE);
+		return intrusive(new RecolorImage2(input,red,green,blue,white));
+	} else {
+		SCRIPT_PARAM(Color, color);
+		return intrusive(new RecolorImage(input,color));
+	}
 }
 
 SCRIPT_FUNCTION(enlarge) {