sys.stdout defaults to text mode, we need to use the underlying buffer
instead when writing binary data.
Signed-off-by: Chirantan Ekbote <chirantan.ekbote@gmail.com>
In order to be more consistent with different subtitle formats.
From:
* --write-srt to --write-sub
* --only-srt to --only-sub
* --all-srt to --all-subs
* --srt-lang to --sub-lang'
Refactored also all the mentions of srt for sub in all the source code.