* Rename feature flags and make package public
This commit renames the feature flags "classic-matchers-parsing"
and "utf8-matchers-parsing" to "classic-matchers" and "utf8-matchers".
This better represents their use, for example, when validating
both alerts and silences created via the API.
It also makes the feature flags package public for two reasons:
1. AllowedFlags is a public variable
2. We would rather use these consts in Mimir then have to hardcode
the strings ourselves, and be subject to breaking changes in future
Signed-off-by: George Robinson <george.robinson@grafana.com>
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Signed-off-by: George Robinson <george.robinson@grafana.com>
ca5089d33e