Implement input for MRs over child entities

Also throwing in a proof-of-concept MR that I'd like to run in production, and then scrap once the meaty MR is finished (e.g. exploding Recurring billing events into OneTimes).
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=119881471

java/com/google/domain/registry/mapreduce/inputs/EppResourceBaseReader.java

@@ -61,8 +61,7 @@ abstract class EppResourceBaseReader<T> extends InputReader<T> {
   private transient QueryResultIterator<EppResourceIndex> queryIterator;
 
   EppResourceBaseReader(
-      Key<EppResourceIndexBucket>
-      bucketKey,
+      Key<EppResourceIndexBucket> bucketKey,
       long memoryEstimate,
       ImmutableSet<String> filterKinds) {
     this.bucketKey = bucketKey;