Added Transform objects to love.math (resolves issue #1228).

- Added love.math.newTransform.
- Added love.graphics.applyTransform and love.graphics.replaceTransform.
- love.graphics.draw/print/printf, Text:add/addf, and SpriteBatch:add can accept a Transform argument.
- love.graphics.push can accept an optional Transform as a second argument, which will apply the Transform after pushing the matrix stack,
- Shader:send can accept Transform objects when sending to a mat4 uniform variable.

--HG--
branch : minor

src/modules/math/MathModule.h

@@ -45,6 +45,7 @@ namespace math
 {
 
 class BezierCurve;
+class Transform;
 
 struct Triangle
 {
@@ -176,6 +177,9 @@ public:
 	 **/
 	BezierCurve *newBezierCurve(const std::vector<Vector> &points);
 
+	Transform *newTransform();
+	Transform *newTransform(float x, float y, float a, float sx, float sy, float ox, float oy, float kx, float ky);
+
 	// Implements Module.
 	virtual ModuleType getModuleType() const
 	{