TextEditor: Re-work comment definition handling

No need for most of the machinery.

Change-Id: I9078174582d83da94c6c7f20282fd3a5f1742911
Reviewed-by: Christian Stenger <christian.stenger@digia.com>
Reviewed-by: hjk <hjk121@nokiamail.com>

src/libs/utils/uncommentselection.h

@@ -45,11 +45,13 @@ class QTCREATOR_UTILS_EXPORT CommentDefinition
 public:
     CommentDefinition();
 
+    enum Style { CppStyle, HashStyle };
+    void setStyle(Style style);
+
+    bool isValid() const;
     bool hasSingleLineStyle() const;
     bool hasMultiLineStyle() const;
 
-    void clearCommentStyles();
-
 public:
     bool isAfterWhiteSpaces;
     QString singleLine;