Added support in HttpTask for writing Request body when HTTP method is PUT or POST

When using the DemoActivity class, I noted that the JSON text was not being sent to the server so I added logic to HttpTask.makeRequest() to detect when PUT or POST methods are being used and then write the body of the Request object to the outputstream.

I have other commits that I'll post once I'm sure I know what I'm doing. First time using git.

Eric