Parses arguments passed from command line.

Examples:

iex> Kitto.Generator.parse_options(["my_widget"])
{[], ["my_widget"], []}

iex> Kitto.Generator.parse_options(["-p", "dashboard_path", "my_dashboard"])
{[path: "dashboard_path"], ["my_dashboard"], []}

iex> Kitto.Generator.parse_options(["--path", "dash", "my_dashboard"])
{[path: "dash"], ["my_dashboard"], []}