Added configuration section to README

Author: Visual-Vincent

README.md

@@ -1,14 +1,25 @@
 # GuiStack
-
-A GUI for your AWS or LocalStack environment.
+A web-based GUI for your AWS or LocalStack environment.
 
 ## System requirements
 - ASP.NET Core Runtime for .NET 6.0 or newer ([Download](https://dotnet.microsoft.com/en-us/download/dotnet))
-- Any OS supported by the above runtime
+- Any operating system supported by the above runtime
+
+## Configuration
+GuiStack can be configured by setting various environment variables before starting the application. Most of them are provided in the `run.sh` or `run.bat` file included within the release.
+
+| Variable name           | Default value (in `run.sh`) |
+| ----------------------- | --------------------------- |
+| AWS_ACCESS_KEY_ID       | localstack                  |
+| AWS_SECRET_ACCESS_KEY   | localstack                  |
+| AWS_REGION              | eu-central-1                |
+| AWS_S3_ENDPOINT_URL     | http://localhost:4566       |
+| AWS_SQS_ENDPOINT_URL    | http://localhost:4566       |
+| AWS_S3_FORCE_PATH_STYLE | true                        |
 
 ## Building
 Requires:
-- .NET 6.0 SDK or newer
+- .NET 6.0 SDK or newer ([Download](https://dotnet.microsoft.com/en-us/download/dotnet))
 
 Optional:
 - Visual Studio 2022