Add cross compiler script [skip ci]

cross_compile.sh

@@ -0,0 +1,45 @@
+#!/bin/bash
+
+dir=$(CDPATH= cd -- "$(dirname -- "$0")" && pwd)
+
+mkdir -p $dir/out/
+rm -f $dir/out/*
+
+platforms=(
+    "linux/arm"
+    "linux/amd64"
+    "linux/arm64"
+    "linux/386"
+    "darwin/amd64"
+    "darwin/arm64"
+    "windows/386"
+    "windows/amd64"
+    "windows/arm64")
+
+for platform in "${platforms[@]}"
+do
+    platform_split=(${platform//\// })
+    GOOS=${platform_split[0]}
+    GOARCH=${platform_split[1]}
+    output_name="farside"
+
+    tar_name="farside_${GOOS}_${GOARCH}.tar.gz"
+    if [ $GOOS = "darwin" ]; then
+        tar_name="farside_macOS_${GOARCH}.tar.gz"
+    fi
+
+    if [ $GOOS = "windows" ]; then
+        output_name+=".exe"
+    fi
+
+    compile_cmd="GOOS=$GOOS GOARCH=$GOARCH go build -ldflags='-s -w' -o $output_name ."
+    echo "└ $compile_cmd"
+    eval $compile_cmd
+    if [ $? -ne 0 ]; then
+        echo "An error has occurred! Aborting the script execution..."
+        exit 1
+    fi
+
+    tar -czvf out/$tar_name $output_name
+    rm -f $output_name
+done