docs: file mode available only as config option

Not as a third option to the constructor, as previously reported.

Updates the one example in the docs, which also demonstrated the config
value, and the mention in the CHANGELOG.

CHANGELOG.md

@@ -6,7 +6,7 @@ All notable changes to this project will be documented in this file, in reverse
 
 ### Added
 
-- [#23](https://github.com/zendframework/zend-config-aggregator/pull/23) adds the ability to specify the file mode for the generated cache file, when generating a cache file. The mode can be provided as the third option to the `ConfigAggregator` constructor, or via the `Zend\ConfigAggregator\ConfigAggregator::CACHE_FILEMODE` configuration option. Modes should be expressed as octal values (e.g., `0640`).
+- [#23](https://github.com/zendframework/zend-config-aggregator/pull/23) adds the ability to specify the file mode for the generated cache file, when generating a cache file. The mode can be provided via the `Zend\ConfigAggregator\ConfigAggregator::CACHE_FILEMODE` configuration option. Modes should be expressed as octal values (e.g., `0600`).
 
 ### Changed
 

docs/book/caching.md

@@ -59,12 +59,11 @@ $aggregator = new ConfigAggregator(
     [
         new ArrayProvider([
             ConfigAggregator::ENABLE_CACHE => true,
-            ConfigAggregator::CACHE_FILEMODE => 0600
+            ConfigAggregator::CACHE_FILEMODE => 0600 // only owner can read and write
         ]),
         new PhpFileProvider('*.global.php'),
     ],
-    'data/config-cache.php',
-    0600 // only owner can read and write
+    'data/config-cache.php'
 );
 ```