Clang: introduce more data in TokenInfo

Data added:
- return type spelling for functions
- parent spelling
- access specifier for class fields and methods
- storage class

New highlighting types are added, therefore
types are now categorized by class, struct, etc.

Change-Id: I1739b94a6f777045fde655060d8b9a12b6e0889b
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@qt.io>

src/tools/clangbackend/source/cursor.h

@@ -27,6 +27,8 @@
 
 #include "clangtype.h"
 
+#include <clangsupport/clangsupport_global.h>
+
 #include <clang-c/Index.h>
 
 #include <iosfwd>
@@ -107,6 +109,8 @@ public:
     unsigned overloadedDeclarationsCount() const;
     Cursor overloadedDeclaration(unsigned index) const;
     Cursor specializedCursorTemplate() const;
+    AccessSpecifier accessSpecifier() const;
+    StorageClass storageClass() const;
 
     CXFile includedFile() const;