Add more details to the Debian dependencies (#210)

* Provide more specific instructions for Debian-based distros

* clarify that you should run command as root

readme.md

@@ -16,8 +16,7 @@ Ly is a lightweight TUI (ncurses-like) display manager for Linux and BSD.
  - tput
  - shutdown
 
-### Debian-based distros
- - libpam0g-dev
+On Debian-based distros running `apt install build-essential libpam0g-dev libxcb-xkb-dev` as root should install all the dependencies for you.
 
 ## Support
 The following desktop environments were tested with success