snapcraft recommends bad naming standards

[Merlijn Sebrechts]

When you register a name, snapcraft currently shows this message:

    ```
    We always want to ensure that users get the software they expect
    for a particular name.

    If needed, we will rename snaps to ensure that a particular name
    reflects the software most widely expected by our community.

    For example, most people would expect ‘thunderbird’ to be published by
    Mozilla. They would also expect to be able to get other snaps of
    Thunderbird as 'thunderbird-$username'.

    Would you say that MOST users will expect 'ikbestani' to come from
    you, and be the software you intend to publish there?
    ```

This is the source: https://github.com/snapcore/snapcraft/blob/131c99fd9da6272e138479798af643a079dfc3f9/snapcraft/cli/store.py#L48

This message has a couple of issues:

* It implies third parties cannot publish snaps and guides users towards using their username as a suffix.
* It talks about "renaming snaps" even though that is not possible.

As a result, many people initially add their username as a suffix to the snap they are creating. Even though that is discouraged by many snapcraft developers, many snaps in the snap store are managed by third parties, and the docs discourage suffixes: https://snapcraft.io/docs/registering-your-app-name.

[Merlijn Sebrechts (merlijn-sebrechts)]

I think this more closely aligns with the vision and current limits of the snap store (i.e. renames are impossible and we don't want an unofficial snap to become popular and be abandoned when an official snap is released)

* We always want to ensure that users get the software they expect for a particular name.
* Would MOST people expect "<snap-name>" to be the software you intend to publish here?
* Are you the original upstream developer or are you planning on upstreaming the snap, or are you ok to hand off the snap if/when the upstream developer chooses to?