Add documentation for replication.shard configuration.

Author: kylebernhardy

docs/deployments/configuration.md

@@ -270,6 +270,10 @@ When true, Harper will verify certificates against the Node.js bundled CA store.
 
 Replication will first attempt to catch up using the audit log. If unsuccessful, it will perform a full table copy. When set to `false`, replication will only use the audit log.
 
+`shard` - _Type_: integer;
+
+This defines the shard id of this instance and is used in conjunction with the [Table Resource functions](../developers/replication/sharding#custom-sharding) `setResidency` & `setResidencyById` to programmatically route traffic to the proper shard.
+
 ***
 
 ### `clustering` using NATS

docs/developers/replication/sharding.md

@@ -65,7 +65,12 @@ class MyTable extends tables.MyTable {
 ```
 
 ## Configuration for Static Sharding
-Alternatively, you can configure static sharding, where each node is assigned to a specific shard, and each record is replicated to the nodes in that shard based on the primary key. The `shard` is identified by a number. To configure the shard for each node, you can specify the shard number in the `replication`'s `routes` in the configuration:  
+Alternatively, you can configure static sharding, where each node is assigned to a specific shard, and each record is replicated to the nodes in that shard based on the primary key. The `shard` is identified by a number. To configure the shard for each node, you can specify the shard number in the `replication`'s `shard` in the configuration:
+```yaml
+replication:
+  shard: 1
+```
+Alternatively, you can configure the `shard` under the `replication` `routes`.  This allows you to assign a specific shard id based on the routing configuration.  
 ```yaml
 replication:
   routes: