use logger instead of plog

'plog' is hard to type, and logger is instinctive.

vim/snippets/php.snippets

@@ -3,5 +3,5 @@ snippet ppre
 	print_r('<pre>'); print_r($${1:check_variable}); exit;
 snippet vardump
 	var_dump($${1:check_variable}); exit;
-snippet plog
+snippet logger
 	Logger::debug('${1:description} ' . print_r($${2:variable}, true);