Add set-up instructions

Author: atifaziz

README.md

@@ -5,6 +5,8 @@ This documentation contains examples for using [MoreLINQ]. The examples can be
 run and tested interactively in a browser using [`dotnet try`
 (Try .NET)][dotnet-try].
 
+See [Setup](setup.md) for requirements and installation instructions.
+
 
 ## Examples
 

setup.md

@@ -0,0 +1,61 @@
+# Setup
+
+Example code is written directly into Markdown documents, which requires
+nothing more than a text editor. However, to develop, run and test those
+examples interactively and ensure their correctness, you will need
+[Try .NET][dotnet-try] installed as a global tool using:
+
+    dotnet tool install -g dotnet-try --version 1.0.19266.1
+
+Once installed, simply run `dotnet try` in a directory with a clone of the
+repository containing this documentation.
+
+Try .NET requires [.NET Core 3.0 SDK][netcore3] _and_ [2.1][netcore21] to be
+installed prior to its installation and use.
+
+If you have [Docker] installed, you can get Try .NET and its requirements
+setup in a ready-to-run container image without affecting your local setup.
+To do so, create a file named `Dockerfile` with the following content:
+
+```Dockerfile
+FROM microsoft/dotnet:3.0-sdk
+
+ENV PATH="${PATH}:/root/.dotnet/tools"
+
+RUN dotnet tool install -g dotnet-try --version 1.0.19266.1 \
+ && curl -k https://dot.net/v1/dotnet-install.sh \
+    | bash /dev/stdin --install-dir /usr/share/dotnet --version 2.1.503 \
+ && mkdir /doc
+
+WORKDIR /doc
+
+ENTRYPOINT ["dotnet", "try"]
+```
+
+Next, build the image, tagging it `dotnet-try`:
+
+    docker build -t dotnet-try .
+
+Then whenever you wish to develop, run and test the code in the Markdown
+documents, change the current working directory of your shell (`cd`) to where
+you cloned the repository containing the documents and run the image using:
+
+    docker run -ti --rm -p 5000:80 -v "$(pwd):/doc" dotnet-try
+
+If you are using PowerShell, run instead using:
+
+    docker run -ti --rm -p 5000:80 -v "$($PWD)/doc" dotnet-try
+
+If you are using the Windows Command Prompt (`cmd.exe`), run instead
+using:
+
+    docker run -ti --rm -p 5000:80 -v "%cd%/doc" dotnet-try
+
+Finally, open a browser and navigate to `http://localhost:5000/README.md`.
+
+
+[dotnet-try]: https://github.com/dotnet/try
+[dotnet-try-setup]: https://github.com/dotnet/try/blob/301dacfdd8af34586def0722a08452bab6393bc9/README.md#setup
+[netcore21]: https://dotnet.microsoft.com/download/dotnet-core/2.1
+[netcore3]: https://dotnet.microsoft.com/download/dotnet-core/3.0
+[docker]: https://www.docker.com/