Theads: pm2 does not play nicely.

I have redis and sharejs installed. I installed pm2 to server the project. Everything works fine if using one thread, however if your try using more than one thread, I am no longer able to sync fields.

Steps to reproduce on share 0.6.3:
1. npm install pm2 (it might require -g)
2. navigate to sharejs/bin
3. pm2 start exampleserver -i 5 (5 can be replace with any number or "max")

When you open up two browsers the textareas on the example page will be out of sync. Right now 1 thread works, but it would be nice to be able to cluster this app.

Thanks agian for all your hard work. This project is great!