Define basic command line interface

[andreiled]

1. Split the downloader/configuration.ts file into several new files comprising a new top level configuration module.

2. Define basic command line interface.

   1. Rename the downloader module to actions/download with the intent
      of placing future implementations of CLI actions under the actions top
      levle module.
   2. Use commander to define basic command line interface:
      • Default no-name command to download all new files from a specified removable drive.
      • init command to initialize a global configuration for this tool.

Manual Testing

1. Build locally: npm run build.

2. Run with various arguments and review the result.

   • $ node dist
     error: missing required argument 'drive-path'
     

   • $ node dist --help
     Usage: dist <drive-path>
     
     Download all new files from the specified removable drive (e.g. a memory card).
     Relies on the global configuration to identify supported directories on the removable drive and to determine where their contents should be saved.
     
     Arguments:
       drive-path  Removable drive (e.g. memory card) path
     
     Options:
       -h, --help  display help for command
     
     Commands:
       init        Initialize a global configuration
     

   • $ node dist init --help
     Usage: dist init [options]
     
     Initialize a global configuration
     
     Options:
       -h, --help  display help for command
     

   • $ node dist X:
     [X:] Found 1 supported directory: X:/DCIM
     [X:/DCIM] 101MSDCF is the latest previously processed sub-directory and could have new files: will process all sub-directories and files starting from it: 101MSDCF
     [X:/DCIM/101MSDCF] All sub-directories and/or files were processed before: ...