debian/copyright: change 'Comments:' to the correct 'Comment:'
add missing files to debian/copyright
update changelog
add -Wformat and -WError=format-security to the build-flags
update changelog
Don't export the ff_* symbols from libswresample, because they shouldn't be part of the ABI.
update changelog
use the upstream Makefile to build the apidoc instead of calling the doxy-wrapper directly
update changelog