[JSON_PROCESSING_SPEC-47] Removing two constructors in JsonException,
JsonParsingException, JsonGenerationException
[JSON_PROCESSING_SPEC-43] Fixing accessor methods javadoc to throw NPE
when there is no mapping
[JSON_PROCESSING_SPEC-45] Adding accessor methods that take default
values
[JSON_PROCESSING_SPEC-50] Fixing typo in JSON text
Fixing typo: s/writeobject/writeObject