Add installation instructions to the release

scripts/release.sh

@@ -23,7 +23,25 @@ docker build -f build.Dockerfile -t lemur-build .
 MSYS_NO_PATHCONV=1 docker run -it --rm -v .:/app -w /app --entrypoint bash lemur-build /app/scripts/do-bundle.sh
 
 read -r -d EOF 'body' <<EOF
-# v${version}
+## How to install
+
+The emulator can be found in the "Downloads" section of this release.
+
+### Windows users
+
+Download \`lemur.exe\`.
+
+### MacOS users
+
+If your Mac uses an Intel processor, download and install \`Lemur-Intel.dmg\`.
+
+If it uses Apple Silicon, download and install \`Lemur-Apple-Silicon.dmg\`.
+
+If you're not sure which to choose, use [this guide](https://support.apple.com/en-us/116943) to find out.
+
+### Linux users
+
+You can either download and run \`lemur-linux\`, or download and install the attached .deb file.
 EOF
 
 read -r -d EOF 'payload' <<EOF