Change from binary serialization to JSON serialization.

[daisukenishino2]

Requirement

Regarding the data format of the task to be registered.
Can not read it with binary. JSON is easier to manage.

• https://github.com/OpenTouryoProject/AsynchronousProcessingService/blob/master/root/programs/CS/Samples/AsyncSvc_sample/TestAsyncSvc_Sample/Program.cs#L77
• https://github.com/OpenTouryoProject/AsynchronousProcessingService/blob/master/root/programs/CS/Samples/AsyncSvc_sample/AsyncSvc_sample/LayerB.cs#L201