Stub out all appendix headers (3.0.4)

So that additional PRs can avoid merge conflicts.

Author: handrews

versions/3.0.4.md

@@ -3698,6 +3698,8 @@ Version   | Date       | Notes
 1.1       | 2012-08-22 | Release of Swagger 1.1
 1.0       | 2011-08-10 | First release of the Swagger Specification
 
+## <a name="dataTypeConversion"></a>Appendix B: Data Type Conversion
+
 ## <a name="usingRFC6570Implementations"></a>Appendix C: Using RFC6570 Implementations
 
 Serialization is defined in terms of RFC6570 URI Templates in two scenarios: