[WIP] Rails 4 upgrade

**DO NOT MERGE YET, WORK IN PROGRESS!**

To get some first feedback I'm already creating this pull request. Of course we will cleanup the commits when it's done for merging.

There will me multiple barclamp pull requests linked against this pull request.
Not going to review the changes in the routes, but stupid questions: shouldn't the version (1.0) be before everything else, instead of after? It hardly makes sense to me right now. Also, is it possible to hide the version when we just browse things  through the webui? Sometimes we see it and sometimes we don't, which is kind of lame.

(of course, all this is actually not related to this PR, but I was just thinking of that)