find, load, flatten json or ini application configuration

 This Node.js module finds and loads configuration files in the usual
 places, loads them, and flatten them in that order:
  - command line arguments (parsed by minimist)
  - environment variables prefixed with $appname_
  - config file path given as `--config` argument
  - .rc in parents folders, in home, or /etc
  - .config/$appname or .config/$appname/config in home
  - /etc/$appname/config
 It is also possible to set a custom command-line options parser
 or a custom configuration file parser.
 .
 Node.js is an event-based server-side JavaScript engine