Remove the scriptz submodule and hard-commit the files.

The submodule is a leftover from when this project was intended to work
as a series of microservices. It was meant to provide common
functionality to the builds for every microservice. That's no longer the
case, and the submodule is a pain-point both in on-boarding new
developers and running the Docker build.

script/include/alpine_setup_functions.inc.sh

@@ -0,0 +1,36 @@
+# alpine_setup_functions: Functions used by the run_alpine_setup script
+
+update_system_packages() {
+  local apk_cache_dir="/etc/apk/cache"
+
+  apk update
+  apk upgrade
+
+  if [ -d "${apk_cache_dir}" ] || [ -L "${apk_cache_dir}" ]; then
+    apk cache clean
+  fi
+}
+
+install_package() {
+  local package_name=${1}
+
+  apk add "${package_name}"
+  return $?
+}
+
+add_group() {
+  local group_name="${1}"
+  local gid="${2}"
+
+  addgroup -g "${gid}" -S "${group_name}"
+  return $?
+}
+
+add_user() {
+  local username="${1}"
+  local primary_group="${2}"
+  local uid="${3}"
+
+  adduser -u "${uid}" -D -S -G "${primary_group}" "${username}"
+  return $?
+}