* updated tests to support BigDecimal as the backing type for numbers
* updated some test resource handling to java7 try-with-resources format
* cleaned up some other minor compiler warnings
* Cleans up some warnings
* Adds new test for bug https://github.com/stleary/JSON-java/issues/332
* Adds some resource handling for string writers using pre-java1.7
support. I know StringWriters don't need a close method called, but the
tests should still handle their resources properly.
This set of tests demonstrates what happens when JSONString returns various results from its toJSONString() method. Tests for null returns and exceptions thrown. Also tests what happens for non-JSONString objects. The intent is to cover JSONObject's valueToString() and writeValue() methods.
