Install steps are only compatible with Debian-based systems

The Kitura distribution for Linux is currently only available as a `.deb` package. For those of us using other distributions, this leads to a bit of a headache, despite the fact that the built binary nested inside the debpackage is highly portable---it works perfectly on my Manjaro system without any special treatment.

It might be beneficial to the community to provide the raw Linux binary in the _Releases,_ as a convenience for those who go looking for it.