cleaned up code

- removed unnecessary assertions
- simplified simple if/return patterns

ChangeLog.md

@@ -5,6 +5,9 @@ All notable changes to this project will be documented in this file. This projec
 
 [Full Changelog](https://github.com/nlohmann/json/compare/v2.0.1...HEAD)
 
+- value\(\) does not work with \_json\_pointer types [\#283](https://github.com/nlohmann/json/issues/283)
+- Easy serialization of classes [\#280](https://github.com/nlohmann/json/issues/280)
+
 - Build error for std::int64 [\#282](https://github.com/nlohmann/json/issues/282)
 
 - hexify\(\) function emits conversion warning [\#270](https://github.com/nlohmann/json/issues/270)