Previously the argument of the "-sub" option was always interpreted as
a local filename when trying to read it as a libass file. Use the
stream layer to read it instead, so that protocols like 'http://' are
also supported like they are for the main video/audio file.
Based on patch by Yuriy Kaminskiy <yumkam@mail.ru>
libass doesn't support fontconfig < 2.4.2 so fallbacks for these
ancient versions aren't needed anymore. Also update the man page
(English, German) to reflect the change. Additionally note that
-embeddedfonts controls the use of ASS script embedded fonts too.
-embeddedfonts is now always enabled by default. Fonts are never
extracted into a directory anymore but passed to libass via memory.
Uoti Urpala
Grigori Goronzy