update proxy configration notes for powershell

Readme.md

@@ -39,9 +39,11 @@ choco install windows\packages\desktop.config
 * Configure squid proxy on windows host and change username in configuration file
 Copy files\squid.conf C:\Squid\etc\squid\squid.conf
 * Restart Squid proxy using windows system service
+
 * Configure vagrant to use the proxy
+    * Powershell `proxy.ps1`
+    * Git-Bash `source proxy.sh`
 ```
-source proxy.sh
 vagrant plugin install vagrant-proxyconf
 vagrant plugin install vagrant-disksize
 ```

doc/Powershell_Environment.md

+* List environment variables
+```
+Get-Item -Path Env:
+```
+* Setting variables
+```
+Set-Item -Path Env:HTTP_PROXY -Value "http://127.0.0.1:3128"
+```
+* showing environment variables
+```
+echo $env:HTTP_PROXY
+Get-Item -Path Env:HTTP_PROXY
+```

proxy.ps1

+Set-Item -Path Env:HTTP_PROXY -Value "http://127.0.0.1:3128"
+Set-Item -Path Env:HTTPS_PROXY -Value "http://127.0.0.1:3128"
+Set-Item -Path Env:VAGRANT_HTTP_PROXY -Value "http://127.0.0.1:3128"
+Set-Item -Path Env:VAGRANT_NO_PROXY -Value "127.0.0.1"