New folder structure proposal for syskit merge

replaces:
https://github.com/planthaber/rock-webapp/pull/8
Why don't you require rock/webapp/syskit/api ?

Also, the definition of the logger (which in this case should be)

```
module Rock
  module WebApp
    module Tasks
      include Logger::Hierarchy
    end
  end
end
```

should be in this file. It also allows to document the module where it makes most sense. Same comment goes for the tasks part