Added love.mouse.hasCursor. Returns true if mouse cursors are available.

--HG--
branch : minor

src/modules/mouse/sdl/Mouse.cpp

@@ -112,6 +112,12 @@ love::mouse::Cursor *Mouse::getCursor() const
 	return curCursor.get();
 }
 
+
+bool Mouse::hasCursor() const
+{
+	return SDL_GetDefaultCursor() != nullptr;
+}
+
 int Mouse::getX() const
 {
 	int x;

src/modules/mouse/sdl/Mouse.h

@@ -53,6 +53,8 @@ public:
 
 	love::mouse::Cursor *getCursor() const;
 
+	bool hasCursor() const;
+
 	int getX() const;
 	int getY() const;
 	void getPosition(int &x, int &y) const;