Update to Ubuntu 18.04 install commands

README.md

@@ -122,9 +122,9 @@ Packages for Arch Linux, CentOS, Debian, Fedora and Ubuntu are auto-generated wi
 
 #### From source
 
-Download the latest stable release or clone this repository (*risky*), install deps and compile. On Ubuntu 16.04:
+Download the latest stable release or clone this repository (*risky*), install deps and compile. On Ubuntu 18.04:
 
-    $ sudo apt-get install pkg-config libncursesw5-dev libreadline6-dev
+    $ sudo apt-get install pkg-config libncursesw5-dev libreadline-dev
     $ make
     $ sudo make strip install