Use the same ObjectMapper by default in Java and Scala
Updated screenshot for creating a new application
Merge pull request #2942 from jroper/activator-new-screenshot

Updated screenshot for creating a new application
Remove tutorials

* Removed the tutorials
* Created a new tutorials page that points people to Activator tutorials
* While I was at it, ran the external link validator and removed/updated
  a few dead links
Merge pull request #2943 from jroper/remove-tutorials

Remove tutorials
Merge pull request #2933 from gmethvin/jackson

Use the same ObjectMapper by default in Java and Scala
Add methods to Java Json API
Merge pull request #2945 from gmethvin/java-json

Add methods to Java Json API
Merge remote-tracking branch: upstream/master