Provide dotfiles CLI

[ChristianGrete]

As a user, I want to be able to run common dotfiles tasks using a command line interface.

Acceptance Criteria

• The command is named dotfiles
• A rich and user friendly usage text is available
  • A short description is included
  • The currently used version is included
  • The location where dotfiles is installed is included
• When executed without any options or subcommands, the usage text is printed
• When executed with the option -?, -h or --help, the usage text is printed
• When executed with the option -v or --version, the currently used version is printed
• When executed with a subcommand, the corresponding script is executed
  • Arguments can follow the subcommand and are passed to that corresponding script
• An add subcommand is provided
  • It takes a profile name <profile> as argument
  • When executed, the corresponding repository to that profile name is looked up on GitHub and cloned when available
  • The target directory for cloning is $DOTFILES/opt
  • When cloned, the profile is checked for an installer script
    • When an installer script is available, it is executed
• A help subcommand is provided
  • It takes a subcommand name <command> as argument
  • When executed, the usage text of a specific subcommand is printed
• A remove subcommand is provided
  • It takes a profile name <profile> as argument
  • When executed...
  • ...the corresponding profile located in $DOTFILES/opt is checked for an uninstaller script
    • When available, that uninstaller script is executed
  • ...the profile $DOTFILES/opt/dotfiles-<profile>-profile gets removed
• An update subcommand is provided
  • When executed, it updates the dotfiles repository by checking out its master branch and pulling from the remote repository on GitHub

[ChristianGrete]

Feature Branch: cli Pull Request: #1