po: Update translations.
Remove NEWS: never used it.
build-sys: Use foreign for automake; no more need of ChangeLog nor
NEWS file.
build-sys: Don't ignore ChangeLog, and get rid of INSTALL.
verify: Don't declare "using Id3Tag".
mlm: In main(), return the result of runnning the application.
mlm: In media, don't create unnecessary wrapper method.
mlm: In application, don't generate unnecessary wrapper methods, don't
call the parent method in an override if not necessary, and some other
cleanups.
mlm: In ApplicationWindow, add translatable strings, and some other
little fixes.