Timeout makes it too easy to write crappy code.
It's also much easier to handle EINTR without timeout.

This fixes a minor bug: revents was undefined if poll() failed.

Do not read revents in case of error.
Do not busy loop if POLLERR or POLLHUP get set.

Close #2052, #4039, #4390, #2796
Apparently Goom developers don't understand SIMD registers...

Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

includes a fix to correctly link libmpcdec and latest contrib updates

Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

Some pages are really huge, the only way we are sure we'll
be able to parse them is to download them entirely

This simplifies error and memory handling.
A few memory leaks were fixed.