Consistent synopsis for "install all" and "install components" scripts

[skalee]

The install_gpg_all.sh script requires passing suite version with -i argument.
The install_gpg_component.sh script requires passing component version with --version argument.

1. This inconsistency should be resolved.
2. --version is a bad name for argument, because <program> --version conventionally prints out program version. Perhaps --at-version or --at?

@ronaldtse, any idea what -i could mean? It has been introduced in your commit.

[ronaldtse]

Sorry, I don’t actually remember. I wonder if it stood for “install” 😢

—at is definitely better than —version.

[skalee]

I believe this one can be considered fixed as of #17.

[ronaldtse]

Thanks @skalee !