update autoloader to consider namespaces for third party libraries: placed and loaded from vendor/namespace/classpath.php

update readability to a newer implementation based on Readability.js (https://github.com/andreskrey/readability.php)
add vendor/Psr/Log interface required for the above

vendor/andreskrey/Readability/Nodes/DOM/DOMProcessingInstruction.php

@@ -0,0 +1,10 @@
+<?php
+
+namespace andreskrey\Readability\Nodes\DOM;
+
+use andreskrey\Readability\Nodes\NodeTrait;
+
+class DOMProcessingInstruction extends \DOMProcessingInstruction
+{
+    use NodeTrait;
+}