Final tweaks to the CLI before release #74

1. Forester has a --no-browser option, but I am not aware that the default behaviour is to open a browser automatically. At least it doesn't do so for me. I think that this option should simply be removed.

2. I think that the default behaviour of running forester should be to show the help page, rather than to start the preview server. The live server, when not initiated by the LSP, is likely to be confusing to users are expecting it to include file-watching. I also think that forester start should probably be renamed to forester serve or forester preview.

What do you think @kento.tngl.sh ?