Small bug fix and documentation for remote interface

Regarding the documentation, I wasn't sure how deep to go into my use case (embedding SelectorGadget in a web page), so the example code is kind of impractical. The setInterval stuff seems especially odd... in my local branch, I've modified SelectorGadget.setPath to trigger an event whenever new predictions are made, but I didn't want to muddy up the commit/pull since I wasn't sure how far my use case falls outside the scope you want for SelectorGadget.