Update README.md
Your change suggests installing the Debian or Ubuntu repository binary for bmon, but the original tells how to compile, install, and run the actual code cloned from this repository. They're not equivalent steps.
There is already a duplicate section on how to compile, install and run in the Readme: https://github.com/tgraf/bmon#compile-yourself For CentOS (https://github.com/tgraf/bmon#centos-7-installation), Fedora (https://github.com/tgraf/bmon#fedora-installation) and MacOs (https://github.com/tgraf/bmon#brew) the installation describes the "install only" way installing directly from the package manager. This PR will bring the documentation in line with all other plattforms