Remove several init scripts for operating systems that are no longer
supported:
* `init.ubuntu` would only be useful on Ubuntu 14.04 LTS which has been
in ESM for over a year
* `init.solaris` is for an operating system that hasn't been updated in
>10 years
* `init.upstart` is for a startup method Ubuntu attempted but abandoned
* `init.fedora.centos.service` is for a version that hasn't recieved
updates since 2017-05-10
* `init.freenas` is identical to `init.freebsd`
* `init-alt.freebsd` appears to attempt to use the web interface
directly, and would break with authentication enabled
3f87996bfc