* add get mute timing by name to MuteTimingService
* update get mute timing request handler to use the service method
* replace validation, uniqueness and used errors with errutils
* update mute timing methods return errutil responses
* use the term "time interval" in errors bevause mute timings are deprecated in Alertmanager and will be replaced by time intervals in the future.
* update create and update methods to return struct instead of pointer
* extract get and save operations to a alertmanagerConfigStore. this removes duplicated code in service (currently only mute timings) and improves testing
* replace generic errors with errutils one with better messages.
* update provisioning services to use new store
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Co-authored-by: Alexander Weaver <weaver.alex.d@gmail.com>
* Extend template and generate
* Generate and fix up alertmanager endpoints
* Prometheus routes
* fix up Testing endpoints
* touch up ruler API
* Update provisioning and fix 500
* Drop dead code
* Remove more dead code
* Resolve merge conflicts
