Add @file markers for capture
headers so that Doxygen will
generate documentation for them.
Additionally, update the doxygen
config file per
7fee50274f
merging the caputils and capchild
directories.
The distinction between the different kinds of capture utility
may not warrant a special subfolfer for each, and sometimes the
distinction is not be clear or some functions could stradle
multiple "categories" (like capture_ifinfo.[ch]).
Simplify by having only a generic 'capture' subfolder. The
separate CMake libraries are kept as a way to reuse object code
efficiently.