Refactor ICANN reporting and billing into common package

This moves the default yearMonth logic into a common ReportingModule, rather than the coarse-scoped BackendModule, which may not want the default parameter extraction logic, as well as moving the 'yearMonth' parameter constant to the common package it's used in. This also provides a basis for future consolidation of the ReportingEmailUtils and BillingEmailUtils classes, which have modest overlap.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=183130311

java/google/registry/reporting/icann/sql/total_domains.sql

@@ -0,0 +1,38 @@
+#standardSQL
+  -- Copyright 2017 The Nomulus Authors. All Rights Reserved.
+  --
+  -- Licensed under the Apache License, Version 2.0 (the "License");
+  -- you may not use this file except in compliance with the License.
+  -- You may obtain a copy of the License at
+  --
+  --     http://www.apache.org/licenses/LICENSE-2.0
+  --
+  -- Unless required by applicable law or agreed to in writing, software
+  -- distributed under the License is distributed on an "AS IS" BASIS,
+  -- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  -- See the License for the specific language governing permissions and
+  -- limitations under the License.
+
+  -- Determine the number of domains each registrar sponsors per tld.
+
+  -- This is just the number of fullyQualifiedDomainNames under each
+  -- tld-registrar pair.
+
+SELECT
+  tld,
+  registrarName as registrar_name,
+  'TOTAL_DOMAINS' as metricName,
+  COUNT(fullyQualifiedDomainName) as metricValue
+FROM
+  `%PROJECT_ID%.%DATASTORE_EXPORT_DATA_SET%.%DOMAINBASE_TABLE%`
+      AS domain_table
+JOIN
+   `%PROJECT_ID%.%DATASTORE_EXPORT_DATA_SET%.%REGISTRAR_TABLE%`
+      AS registrar_table
+ON
+  currentSponsorClientId = registrar_table.__key__.name
+WHERE
+  domain_table._d = 'DomainResource'
+  AND (registrar_table.type = 'REAL' OR registrar_table.type = 'INTERNAL')
+GROUP BY tld, registrarName
+ORDER BY tld, registrarName