Add auto-complete for CLI commands

[TheColorDarkBlue]

Pressing tab auto-completes rendercv ren to rendercv rendercv instead of rendercv render. This is annoying since rendercv rendercv is not an actual command. I propose the command render be renamed to build, compile, or run in order to circumvent this.

For example, rendercv build, rendercv compile, and rendercv run.

[sinaatalay]

Auto-completion requires some other installation that I am not familiar with. Currently, we have no control over it; it's up to the terminal that users use. I will rename this issue so that someone can possibly implement auto-completion for the CLI.