ImageMagick 6.3.4-3/6.3.7-9 RenderFreetype Memory Leak Patch

It can be preferable to invoke ImageMagick commands from a program instead of linking against the API in order to avoid inheriting any memory leaks from the API. For performance reasons, that's not always an option. If you use the ImageMagick API to render text in long-lived processes, memory consumption grows by many kilobytes every time you call an API function that renders text via FreeType. This patch is a one-liner freeing the unreleased memory. Whether you want to blame the leak on ImageMagick or FreeType, this is the sort of thing that “resource acquisition is initialization” prevents in C++.