JS: Add automatic support to subscribe to transactions.
JS: Add automatic support to subscribe to transactions.

ripple/ripple-lib,darkdarkdragon/ripple-lib,wilsonianb/ripple-lib,ripple/ripple-lib,ripple/ripple-lib,ripple/ripple-lib,wilsonianb/ripple-lib,darkdarkdragon/ripple-lib,darkdarkdragon/ripple-lib,wilsonianb/ripple-lib