NEW: Added support for config condition if PHP extension is loaded

docs/en/02_Developer_Guides/04_Configuration/00_Configuration.md

@@ -339,6 +339,7 @@ You then list any of the following rules as sub-keys, with informational values
   - 'envvarset', in which case the value(s) should be environment variables that must be set
   - 'constantdefined', in which case the value(s) should be constants that must be defined
   - 'envorconstant' A variable which should be defined either via environment vars or constants
+  - 'extensionloaded', in which case the PHP extension(s) must be loaded
 
 For instance, to add a property to "foo" when a module exists, and "bar" otherwise, you could do this:
 

src/Core/Config/CoreConfigFactory.php

@@ -182,6 +182,9 @@ function ($name, $value = null) use ($envvarset, $constantdefined) {
             })
             ->addRule('moduleexists', function ($module) {
                 return ModuleLoader::inst()->getManifest()->moduleExists($module);
+            })
+            ->addRule('extensionloaded', function ($extension) {
+                return extension_loaded($extension);
             });
     }
 }