Add support for building ubuntu:20.04-based docker images + some automation

install-dep-packages.sh

@@ -0,0 +1,49 @@
+#!/bin/sh
+set -e
+
+do_alpine() {
+    local deps="python3 py3-pip openssl tor"
+    local makedeps="python3-dev gcc g++ libffi-dev musl-dev make automake autoconf libtool"
+
+    case "$1" in
+    install)
+        apk --update --no-cache --no-progress add $deps $makedeps
+        ;;
+    remove-makedeps)
+        apk del $makedeps
+        ;;
+    esac
+}
+
+do_ubuntu() {
+    local deps="python3 python3-pip openssl tor"
+    local makedeps="python3-dev gcc g++ libffi-dev make automake autoconf libtool"
+
+    case "$1" in
+    install)
+        apt-get update && \
+        apt-get install --no-install-recommends -y $deps $makedeps && \
+        rm -rf /var/lib/apt/lists/*
+        ;;
+    remove-makedeps)
+        apt-get remove -y $makedeps
+        ;;
+    esac
+}
+
+if test -f /etc/os-release ; then
+    . /etc/os-release
+elif test -f /usr/lib/os-release ; then
+    . /usr/lib/os-release
+else
+    echo "No such file: /etc/os-release" > /dev/stderr
+    exit 1
+fi
+
+case "$ID" in
+    ubuntu) do_ubuntu "$@" ;;
+    alpine) do_alpine "$@" ;;
+    *)
+        echo "Unsupported OS ID: $ID" > /dev/stderr
+        exit 1
+esac