monolog2 support

system/src/Grav/Common/Plugins.php

@@ -320,7 +320,7 @@ class Plugins extends Iterator
 
         // Log a warning if plugin cannot be found.
         if (null === $class) {
-            $grav['log']->addWarning(
+            $grav['log']->warning(
                 sprintf("Plugin '%s' enabled but not found! Try clearing cache with `bin/grav clearcache`", $name)
             );
         }

system/src/Grav/Framework/Flex/FlexIndex.php

@@ -881,7 +881,7 @@ class FlexIndex extends ObjectIndex implements FlexIndexInterface
 
         /** @var Logger $logger */
         $logger = $grav['log'];
-        $logger->addAlert($e->getMessage());
+        $logger->alert($e->getMessage());
 
         /** @var Debugger $debugger */
         $debugger = $grav['debugger'];