Improvements to autoload docs

doc/04-schema.md

@@ -215,21 +215,26 @@ Example:
 Autoload mapping for a PHP autoloader.
 
 Currently [PSR-0](https://github.com/php-fig/fig-standards/blob/master/accepted/PSR-0.md)
-autoloading and classmap generation are supported.
+autoloading and classmap generation are supported. PSR-0 is the recommended way though
+since it offers greater flexibility (no need to regenerate the autoloader when you add
+classes).
 
 Under the `psr-0` key you define a mapping from namespaces to paths, relative to the
-package root.
+package root. Note that this also supports the PEAR-style convention.
 
 Example:
 
     {
         "autoload": {
-            "psr-0": { "Monolog": "src/" }
+            "psr-0": {
+                "Monolog": "src/",
+                "Vendor\\Namespace": "src/",
+                "Pear_Style": "src/"
+            }
         }
     }
 
-Optional, but it is highly recommended that you follow PSR-0 and use this.
+If you need to search for a same prefix in multiple directories,
-If you need to search for a same namespace prefix in multiple directories,
 you can specify them as an array as such:
 
     {
@@ -238,15 +243,24 @@ you can specify them as an array as such:
         }
     }
 
+If you want to have a fallback directory where any namespace can be, you can
+use an empty prefix like:
+
+    {
+        "autoload": {
+            "psr-0": { "": "src/" }
+        }
+    }
+
 You can use the classmap generation support to define autoloading for all libraries
-that do not follow PSR-0. To configure this you specify all directories
+that do not follow PSR-0. To configure this you specify all directories or files
 to search for classes.
 
 Example:
 
     {
         "autoload: {
-            "classmap": ["src/", "lib/"]
+            "classmap": ["src/", "lib/", "Something.php"]
         }
     }