Send focus event when node is being used.

Master is broken currently with NodeJS, in that no frame data is received without "focused" being set to true.  As one possible fix, I have the focused event sent upon ready.  This is similar to the browser implementation, which begins the "Focus Loop" upon ready.  The tests have been simplified (same tests for node and web) and made more independent (`assert.include` relevant item, as opposed to `deepEqual`).

Some things I'm not 100% on:
 - Is it correct to be sending focused, as opposed to not required "focused" when in node?
 - It looks like there are some trivial changes in leap.js, perhaps due to possible new package versions (EventEmitter and Browserify?)

Cheers