use store.loadData rather than store.load

Hi Wilk,

I've finally got back to looking at using WebSocket in my project. 
I found a problem when the server pushes an updated record to the store.
You are using store.load which triggers the proxy to do a fresh read rather than use the data that has been pushed. I changed this to store.loadData which, for me at least, has the desired affect. The pushed data just gets added to the store.

There was a 2nd problem here in that loadData doesn't seem to fire the load event, even though the docs says it does, so I just added this to my fix.

Let me know if you think I'm doing something wrong.

AlanE