[CX-2269] Add installation script for *nix users

Author: chunfeilung

README.md

@@ -5,8 +5,11 @@ Light Train (SLT)](https://trains.chuniversiteit.nl/#slt).
 ## Installation
 
 ### macOS 10.12+ / Linux (x64, ARM)
-Download the latest binary for your platform from the Releases page. Make the
-binary executable using `chmod +x $fileName` and move the binary to `/usr/local/bin/slt`.
+Paste and execute the following command in a terminal window:
+
+```
+/bin/bash -c "$(curl -L https://raw.githubusercontent.com/chunfeilung/slt/main/install.sh)"
+```
 
 ### Windows
 > :warning: slt may not display properly in cmd.exe. Please use Windows Terminal

install.sh

@@ -0,0 +1,38 @@
+#!/usr/bin/env bash
+
+set -e
+
+# Grab base download URL for latest release
+BASE_DOWNLOAD_URL=$(curl -Ls https://api.github.com/repos/chunfeilung/slt/releases/latest \
+  | grep browser_download_url \
+  | grep linux-x64 \
+  | sed -re 's/(.+)"(http.+)-linux-x64"/\2/')
+
+# Determine the right postfix for this runtime platform
+if [[ "$OSTYPE" == "darwin"* ]]; then
+  BINARY_DOWNLOAD_URL="${BASE_DOWNLOAD_URL}-osx-x64"
+
+else
+  if [[ $(uname -m) == *"x86_64"* ]]; then
+    libc=$(ldd /bin/ls | grep 'musl' | head -1 | cut -d ' ' -f1)
+    if [ -z $libc ]; then
+      BINARY_DOWNLOAD_URL="${BASE_DOWNLOAD_URL}-linux-x64"
+    else
+      BINARY_DOWNLOAD_URL="${BASE_DOWNLOAD_URL}-linux-musl-x64"
+    fi
+
+  elif [[ $(uname -m) == *"arm64"* ]] || [[ $(uname -m) == *"aarch64"* ]]; then
+    BINARY_DOWNLOAD_URL="${BASE_DOWNLOAD_URL}-linux-arm64"
+
+  else
+    echo "This runtime platform is currently not supported. :("
+    exit 1
+  fi
+fi
+
+# Download and install the program
+curl -sL $BINARY_DOWNLOAD_URL > /tmp/slt
+chmod +x /tmp/slt
+mv /tmp/slt /usr/local/bin/slt
+/usr/local/bin/slt --speed 10
+echo 'Installation is complete! :-)';