Adds PowerShell script for Greenshot

Curl is needed as Invoke-WebRequest and Invoke-RestMethod don't like uploading files easily. Curl simplifies the process down to one line of code.

rtfm/INTEGRATIONS.md

@@ -43,4 +43,68 @@ result=$(curl -s -F "file=@${1}" https://pictshare.net/api/upload.php | jq -r .u
 
 xclip -selection clipboard -t image/png -i $1
 google-chrome $result
-```
+```
+
+# Screenshot to pictshare (windows)
+
+This script will upload a screenshot from [Greenshot](https://getgreenshot.org/) to PictShare with the help of a PowerShell script.
+
+Requirements:
+- curl (choco install curl)
+- [PowerShell 7](https://docs.microsoft.com/en-us/powershell/scripting/install/installing-powershell-on-windows)
+
+Configure Greenshot:
+- Settings -> Output
+  - Storage location: C:\Temp\
+  - Filename pattern: GreenShot
+  - Image format: jpg
+Create a new External command, under Settings -> Plugins -> Click on External command Plugin -> Configure -> New
+- Name: what ever you want here
+- Command: find and point to pwsh.exe
+- Argument: -F Path\to\this\script -Address consto.com
+
+Create a PowerShell script with the code below.
+
+Feel free to change "C:\Temp\GreenShot.jpg" and "C:\Temp\pictshare_posts.json" to match your needs.
+
+pictshare_posts.json is useful for logging and automating deleting old uploads.
+
+```powershell
+#Requires -Version 7
+
+param (
+    # Change the base url to match your Pictshare server
+    [Parameter(Mandatory)][string]$Address,
+    # Change path of where you expect the jpg file to be
+    [string]$File = "C:\Temp\GreenShot.jpg",
+    # Log file of all requests
+    [string]$LogFile = "C:\Temp\pictshare_posts.json",
+    # Use http and not https
+    [switch]$IsNotHttps,
+    # Do not save url to upload to the clipboard
+    [switch]$NoSaveToClipboard
+)
+begin {
+    $Protocol = if ($IsNotHttps){
+        "http:"
+    }else{
+        "https:"
+    }
+}
+process {
+    # Upload screenshot
+    $Response = $(curl -s -F "file=@$File" $Protocol//$Address/api/upload.php) | ConvertFrom-Json
+    if ($Response.status -like "ok") {
+        if ($NoSaveToClipboard){
+            # Don't save url to clipboard
+        }else{
+            Set-Clipboard -Value $Response.url
+        }
+    }
+    # Output response back from the pictshare server
+    if($Response){
+        $Response | ConvertTo-Json | Out-File -FilePath $LogFile -Append
+    }
+}
+end {}
+```