Overhaul build scripts

* Moved scripts into separate directory.
* Can now do a release build with a single command.
* Automatically create release tarball.

scripts/build_all_platforms.sh

@@ -0,0 +1,14 @@
+#!/bin/bash
+
+function buildArch {
+    echo Building platform $1-$2
+    GOOS=$1 GOARCH=$2 go build -o build/boringproxy-$1-$2$3
+}
+
+buildArch linux amd64
+buildArch linux arm
+buildArch linux arm64
+
+buildArch windows amd64 .exe
+
+buildArch darwin amd64

scripts/build_release.sh

@@ -0,0 +1,7 @@
+#/bin/bash
+
+version=$(git describe --tags)
+
+./scripts/build_all_platforms.sh
+
+tar -czf ./boringproxy_${version}.tar.gz build/