Fill out more coverage

tests/cases/TestTokenizer.php

@@ -16,6 +16,7 @@ use dW\HTML5\StartTagToken;
 use dW\HTML5\WhitespaceToken;
 
 /** 
+ * @covers \dW\HTML5\Data
  * @covers \dW\HTML5\Tokenizer
  * @covers \dW\HTML5\CharacterToken
  * @covers \dW\HTML5\CommentToken

tests/cases/TestTreeConstructor.php

@@ -15,9 +15,12 @@ use dW\HTML5\Tokenizer;
 use dW\HTML5\TreeBuilder;
 
 /** 
+ * @covers \dW\HTML5\Document
+ * @covers \dW\HTML5\Element
  * @covers \dW\HTML5\TreeBuilder
  * @covers \dW\HTML5\Tokenizer
  * @covers \dW\HTML5\ActiveFormattingElementsList
+ * @covers \dW\HTML5\TemplateInsertionModesStack
  * @covers \dW\HTML5\OpenElementsStack
  * @covers \dW\HTML5\Stack
  */