This makes the validation rules much simpler, thus placing less cognitive load on the users of the console and nomulus tool. The changes are:
1. Don't allow hyphens. No real registrars use hyphens in their client IDs, and it's better to reserve these solely as the delimiter between the base client ID and the number representing the environment.
2. Allow the first character to be a number. This has affected multiple real registrars, causing their OT&E and production client IDs to be different. There's no reason for this restriction, as the only reason motivating it was that there are no TLDs that start with a number. However, the OT&E TLDs are created only in sandbox and never have DNS syncing enabled, so this restriction is purposeless.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=229187198
8ac8ecf8f6