add aegisub

[Julien Lepiller]

Hi,

I made three patches to add aegisub. It needs icu support in boost.

Currently, the window acts strangely. Widgets resize when resizing the
window, but not when maximizing it, they don't all show at first. The
video part should resize with the mouse wheel, but the containing frame
only resizes after resizing the window. sliders don't visually move,
but they are functionnal. Sound can't play (it defaults to alsa which
doesn't work on my system, and crashes when selecting pulseaudio with
"Assertion 'c->callback' failed at pulsecore/socket-client.c:126,
function do_call(). Aborting.").

So I need some help here.

Also the testing suite depends on a lua package that is not in guix
yet and has a lot of dependencies not in guix. So I disabled it for now.

0001-gnu-Add-ffms2.patch
Description: Text Data

0002-gnu-boost-Add-icu-support.patch
Description: Text Data

0003-gnu-Add-aegisub.patch
Description: Text Data