Post with content-type Json

[RaviVaranasi]

The webhook listener is doing a http post of body of type string.

Can we use the api and pass JSON content type ?

  public T bodyText(java.lang.String body,  java.lang.String mediaType)

at this line.

I am unable to build the project locally.

[RaviVaranasi]

I was able to build the project. I have issued a pr with the fix.