export utilities

to_media_type (int -> MediaType)
get_field_int, leveraging av_opt*

--HG--
branch : pure-cffi
we need the AVClass option getters.

--HG--
branch : pure-cffi
more streams support.

--HG--
branch : pure-cffi
port probe.py to the new API.

--HG--
branch : pure-cffi
ignore the big buck bunny sample file(s)

go watch the movie, is really nice :)

--HG--
branch : pure-cffi
properly close the Demuxer and avoid leaks.

--HG--
branch : pure-cffi
cosmetics and future work.

--HG--
branch : pure-cffi
functionally revert the previous commit to avoid a segfault

aka: ALWAYS run tox BEFORE to commit, smartypants.

--HG--
branch : pure-cffi
find_stream not yet implemented, so it can fail

And it will.

--HG--
branch : pure-cffi
spacing

--HG--
branch : pure-cffi
test the opaque accessors; restore 100% coverage.

--HG--
branch : pure-cffi
export AVFrame through cffi.

--HG--
branch : pure-cffi
pylint update.

--HG--
branch : pure-cffi
introduce and use a more specific exception

when the user ask for something specific and this is not found.
ProcessingError was too generic.

--HG--
branch : pure-cffi
implement and test pyrana.format.find_stream.

--HG--
branch : pure-cffi
bump the required versions.

--HG--
branch : pure-cffi
rephrasing.

--HG--
branch : pure-cffi
typos (really: relics from python 2.x)

--HG--
branch : pure-cffi
CODEC stubs both for audio and for video.

--HG--
branch : pure-cffi
Merge ../pyrana