travis: Install packages using apt addon
travis: Install packages using apt addon

nikhilsinghmus/csound,nikhilsinghmus/csound,nikhilsinghmus/csound,nikhilsinghmus/csound,nikhilsinghmus/csound,nikhilsinghmus/csound,nikhilsinghmus/csound,nikhilsinghmus/csound,nikhilsinghmus/csound,nikhilsinghmus/csound