Add `sudo` to pygame install for FreeBSD, OpenBSD
Add `sudo` to pygame install for FreeBSD, OpenBSD

@ibara noted in pull request #114 of two commands for installing
Pygame which were incorrect. `sudo` should be used to install
Pygame in FreeBSD and OpenBSD, with their respective package
managers.

hypatia-software-org/hypatia-engine,lillian-lemmer/hypatia,hypatia-software-org/hypatia-engine,lillian-lemmer/hypatia