docs: minor update (#277)

README.md

@@ -1,6 +1,7 @@
-# vulnz cli
+# open-vulnerability-cli
 
-The cli is a spring-boot command line tool built with picocli. The example
+The open-vulnerability-cli is called `vulnz` because open-vulnerability-cli is cumbersome.
+`vulnz` is a spring-boot command line tool built with picocli. The example
 below does run the setup - which creates both the `vulnz` symlink (in `/usr/local/bin`)
 and a completion script. If using zsh, the completion will be added to
 `/etc/bash_completion.d` or `/usr/local/etc/bash_completion.d` (depending