QC LuaPlugin - now with a (slightly) better editor and images

In February I've worked now and then on my Lua plugin for Quartz Composer.

The Good

• Courtesy of Noodlesoft, the editor is nicer, and shows line numbers and a marker when an error is detected.
• There is now a sort of experimental support to image type: still no way to interpret them (and, anyway, why?), but they're properly recognized and passed around

The Bad

• I've also added a composition to do some simple benchmark, and the result is that Lua lags behind a properly written JavaScript (tests done on 10.6)... Not surprising, given that Lua is standing (almost) still, while Apple has put a lot of efforts in JavaScriptCore lately! The lack of a 64-bit LuaJIT is starting to hurt...

The Ugly

• To implement the images, I've had to use undocumented APIs (the QCImage class isn't public), as there was no (simple) way to get what I needed in the "Official" one...