FIX: project path in sublime-project file

Now it's relative, so it's easier to cloning repo to new systems with different directory structures.
Create default config.json if it doesn't exists

Configuration logic no longer throws an error if config.json doesn't exist. Now it creates this file with sample settings in it. It has to be edited though, so it can only serve as a guide.
All dependencies are now listed in package.json

There used to be three packages that had to be npm linked in order for R20 to launch (express-controller, teacup-view and Error2). Now they are installed from GitHub repositories.
0.7.5