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/common/Matrix.cpp

@@ -73,6 +73,12 @@ Matrix4::Matrix4()
 {
 	setIdentity();
 }
+
+
+Matrix4::Matrix4(const float elements[16])
+{
+	memcpy(e, elements, sizeof(float) * 16);
+}
 	
 Matrix4::Matrix4(float t00, float t10, float t01, float t11, float x, float y)
 {