Added initial port of original OSX project.

- This is a copy of the [OSX](https://github.com/bkuhlmann/osx) project
  originally released on 2012-03-31. The OSX project has been
  deprecated. All future development and support will take place with
  this project instead.
- This project uses the *macOS* name in order to better match the
  updated branding and terminology used by Apple.

lib/utilities.sh

@@ -0,0 +1,79 @@
+#! /bin/bash
+
+# DESCRIPTION
+# Defines general utility functions.
+
+# Answers the file name.
+# Parameters:
+# $1 = The file path.
+get_file_name() {
+  printf "${1##*/}" # Answers file or directory name.
+}
+export -f get_file_name
+
+# Answers the file extension.
+# Parameters:
+# $1 = The file name.
+get_file_extension() {
+  local name=$(get_file_name "$1")
+  local extension="${1##*.}" # Excludes dot.
+
+  if [[ "$name" == "$extension" ]]; then
+    printf ''
+  else
+    printf "$extension"
+  fi
+}
+export -f get_file_extension
+
+# Answers the root install path for file name.
+# Parameters:
+# $1 = The file name.
+get_install_root() {
+  local file_name="$1"
+  local file_extension=$(get_file_extension "$file_name")
+
+  # Dynamically build the install path based on file extension.
+  case $file_extension in
+    '')
+      printf "/usr/local/bin";;
+    'app')
+      printf "/Applications";;
+    'prefPane')
+      printf "/Library/PreferencePanes";;
+    'qlgenerator')
+      printf "/Library/QuickLook";;
+    *)
+      printf "/tmp/unknown";;
+  esac
+}
+export -f get_install_root
+
+# Answers the full install path (including file name) for file name.
+# Parameters:
+# $1 = The file name.
+get_install_path() {
+  local file_name="$1"
+  local install_path=$(get_install_root "$file_name")
+  printf "$install_path/$file_name"
+}
+export -f get_install_path
+
+# Cleans work path for temporary processing of installs.
+clean_work_path() {
+  rm -rf "$MAC_OS_WORK_PATH"
+}
+export -f clean_work_path
+
+# Caffeinate machine.
+caffeinate_machine() {
+  local pid=$(ps aux | grep caffeinate | grep -v grep | awk '{print $2}')
+
+  if [[ -n "$pid" ]]; then
+    printf "Whoa, tweaker, machine is already caffeinated!\n"
+  else
+    caffeinate -s -u -d -i -t 3153600000 > /dev/null &
+    printf "Machine caffeinated.\n"
+  fi
+}
+export -f caffeinate_machine