Indexing a changelog attribute

Steps

Use dsconfig to set attribute indexing on an attribute in the changelog backend.

Example:

Index different attributes by adding specific properties. In the following example, the command enables the Changelog Backend and sets the backend to include all user attributes (*) for ADD or MODIFY operations using the changelog-include-attribute property. The changelog-deleted-entry-include-attribute property is set to all attributes (*) to specify a set of attribute types that should be included in a changelog entry for DELETE operations. Attributes specified in this list are recorded in the deletedEntryAttrs attribute on the changelog entry when an entry is deleted. The attributes displayName and employeeNumber are indexed using the index-include-attribute property.
```
$ bin/dsconfig set-backend-prop --backend-name changelog \
  --set "enabled:true" \
  --set "changelog-include-attribute:*" \
  --set "changelog-deleted-entry-include-attribute:*" \
  --set "index-include-attribute:displayName" \
  --set "index-include-attribute:employeeNumber"
```
To add another attribute to index, use the dsconfig --add option, which adds the attribute to an existing configuration setting.

Example:
```
$ bin/dsconfig set-backend-prop --backend-name changelog \
  --add "index-include-attribute:cn"
```