convert standalone script into a PowerShell module

Readme.md

@@ -54,7 +54,14 @@ Developed by [@christruncer](https://twitter.com/christruncer)
 
 # Usage
 
-The easiest way to get up and running with WMImplant is to import the script and run Invoke-WMImplant. This will present you with the main menu and you can instantly start choosing a command to run. Within the main menu, you can also choose to have WMImplant output the command line command you would need to use in order to run WMImplant in a non-interactive manner.
+The easiest way to get up and running with WMImplant is to import the module and run `Invoke-WMImplant`.
+
+    Import-Module .\WMImplant.psd1
+    Invoke-WMImplant
+
+This will present you with the main menu and you can instantly start choosing a command to run. Within the main menu, you can also choose to have WMImplant output the command line command you would need to use in order to run WMImplant in a non-interactive manner.
+
+You can optionally place this module into your modules folder (defined in `$env:PSModulePath`) and it will auto import when you execute `Invoke-WMImplant`.
 
 Thanks to:
     [@evan_Pena2003](https://twitter.com/evan_pena2003) - For your help with code reviews and adding functionality into the tool