Merge pull request #277 from TimothyGu/emerg

Enable libnut/ffmpeg compilation on i686-pc-mingw32 again
Merge pull request #278 from TimothyGu/dca

libdca: add cherry-picked patches that fix crashes, etc.
Add package dlfcn-win32

Signed-off-by: Timothy Gu <timothygu99@gmail.com>