there seems to be something in the tiff header that after effects doesn't like.

workaround: use targa files (thanks to toxi for contributing code for this).
saveFrame("frame-####.tga");
will give you four digit numbered targa files just like saveFrame() with no parameters.

this is currently a low priority because the workaround exists (and even does rle
compression, also thanks to toxi).

developer notes:
the images work fine after being re-saved with photoshop. need to try re-saving and see
what tags change (outside of just all the tags that photoshop adds), it may be correcting
something, or just be happier with those additional tags, in which case we can fix the header
that's output from PImage.

closing this one, since there are other alternatives to TIFF (e.g. TGA and
PNG) that also support ARGB images.

had a fix for the implementation of saveTIFF(), but realized that it would
mean supporting loadTIFF() for the new images--as well as the older image
format too (or having some caveat about using TIFF only created by the
current version of processing).