Add extra logic for all relevant flows

This CL enhances various domain flows (check, create, delete, renew, restore, transfer, update) so that they invoke the appropriate methods on the object implementing the TLD's RegistryExtraFlowLogic (if any). TldSpecificLogicProxy is also updated to invoke RegistryExtraFlowLogic proxy (if any) to fetch the appropriate price. The tests use a made-up extra flow logic object which can be attached to a test TLD to make sure that the proper routines are being invoked.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=132486734

java/google/registry/model/domain/fee/Credit.java

@@ -21,11 +21,12 @@ import java.math.BigDecimal;
 
 /** A credit, in currency units specified elsewhere in the xml, and with an optional description. */
 public class Credit extends BaseFee {
-  public static Credit create(BigDecimal cost, String description) {
+  public static Credit create(BigDecimal cost, FeeType type, Object... descriptionArgs) {
     Credit instance = new Credit();
     instance.cost = checkNotNull(cost);
     checkArgument(instance.cost.signum() < 0);
-    instance.description = description;
+    instance.type = checkNotNull(type);
+    instance.generateDescription(descriptionArgs);
     return instance;
   }
 }