Separate the blocks to make the grouping easier to grasp,
add the file properly to the group and fix the file description
incorrectly used as filename, fixing the following doxy warning:
warning: the name 'Colorspace' supplied as the argument in
the \file statement is not an input file
This commit moves some of the functionality from avfilter/colorspace
into avutil/csp and exposes it as a public API so it can be used by
libavcodec and/or libavformat. It also converts those structs from
double values to AVRational to make regression testing easier and
more consistent.
Signed-off-by: Ronald S. Bultje <rsbultje@gmail.com>