TCC file support

[lurkmoar]

I believe I have implemented support for tone curve effects read from TCC files. Hope this works :) - unfortunately I only had access to 64-bit Linux and Memorial Edition or newer games for testing, though I did manually extract and apply data from TCC files from other games to random images in a test program and the results seemed like what they should be.

[lurkmoar]

You are very welcome :). This commit that should fix all of that (and add the small but very necessary SConscript change that somehow didn't get through last time - yikes!). If anything else looks off formatting-wise feel free to let me know.

[eglaysher]

The code LGTM. A few final pieces of administrata before I merge this:

• Please remove the mention of TCC being unimplemented from the top level README.TXT. That would be the bullet point in section 4 and all of section 5. (I'll take care of scrubbing the documentation branch at release time.)
• Please add an entry for version 0.13 to the NEWS.TXT following the format of the file, but leaving off the date. I'd like you to do this so you can add a "Thanks to ." to the end of your entry on TCC support. I know me. I will forget otherwise, and I don't want this to go uncredited at release time.
• Please squash these three commits into one. I'm a heavy git bisect user and don't want to land on a commit that doesn't compile due to bad build files.

[lurkmoar]

Done and squashed.