Updated the readme (#273)

* Install/Uninstall multiple packages using ppman

* Updated the readme

* updated a variable

Co-authored-by: Thomas <git@hexf.me>

cli/commands/ppman_commands/install.js

@@ -1,6 +1,6 @@
 const chalk = require('chalk');
 
-exports.command = ['install <runtimes...>'];
+exports.command = ['install <packages...>'];
 exports.aliases = ['i'];
 exports.describe = 'Installs the named package';
 

readme.md

@@ -147,7 +147,7 @@ cli/index.js ppman list
 cli/index.js ppman install python
 
 # Install specific version of python
-cli/index.js ppman install python 3.9.4
+cli/index.js ppman install python=3.9.4
 
 # Run a python script using the latest version
 echo 'print("Hello world!")' > test.py