Merewra: Media Recoding Wrapper

I am scratching my itch of converting between the media formats that my
various consumer devices produce and consume, and comparing which of the
available tools produces good (or any at all) results.

There are *profiles* which are implemented by various *backends*
The profiles are just lists of recoder settings:
- container
- audio and video codec
- requested size (for a mobile phone)
- quality
The current backends are:
- ffmepg
- mencoder
- transcode

TODO: specify the license.