Add the START_DATE_SUNRISE phase

The START_DATE_SUNRISE phase allows registration of domains only with a signed mark. In all other respects - it is identical to the GENERAL_AVAILABILITY phase.

Note that Anchor Tenants bypass all checks, and are hence able to register domains without a signed mark.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185534793

java/google/registry/model/registry/Registry.java

@@ -154,6 +154,12 @@ public class Registry extends ImmutableObject implements Buildable {
      */
     LANDRUSH,
 
+    /**
+     * The state in which only trademark holders can submit a "create" request. It is identical to
+     * {@link #GENERAL_AVAILABILITY} in all other respects.
+     */
+    START_DATE_SUNRISE,
+
     /**
      * A state in which no domain operations are permitted. Generally used after sunrise or landrush
      * to allocate uncontended applications and send contended applications to auction. This state