[Bf-committers] Libraries update required

[Sergey Sharybin]

Hey everyone,

Here is a request for platform maintainers to perform the following
libraries update:

- Update OIIO from 1.6.9 to 1.7.8 (will solve T49250)
- Update OSL from 1.7.3 to 1.7.5 (recompilarion is needed since OIIO
update, so can update to latest version as well)
- Update FFmpeg from 2.1.5 to 3.2.1 (we were hitting weird bugs in the
studio with 2.1.5)
- Update OSD from 3.0.1 to 3.1.0 (brings new fixes/improvements for
face-farying data)

That's it for now, just let me know in IRC how this goes.

-- 
With best regards, Sergey Sharybin