Agenda 2014

This change adds the agenda for 2014 as we discussed it in the organizer hangout on Monday, Oct 28 and reflects the current status of the [schedule](https://docs.google.com/spreadsheet/ccc?key=0Aoyemg-smkz1dGJyTF9vcTdaY0ZiZFFqMnAyVUR4MHc#gid=1).

I added all info I could take from the document, applied a new "level" field to all talks and rearranged them a bit within the track to make the kick-off more interesting and help some other talks to have a more active audience (e.g. the Code Puzzles should start after a coffee break and be the last talk in the track).

Hope everything is fine but please please please check before merging + releasing into master.

Browsing this version is easy: 
- git clone the repo if not already done
- switch to this feature branch
- call `grunt server` to start the local version

Let me know if anything is wrong.

![devfest-agenda](https://cloud.githubusercontent.com/assets/45467/4802117/4509d752-5e3e-11e4-88e3-51d651444031.png)