Upgrading sbt-native-packager and docs
Revamped documentation due to #2915 and #2898
Can't resolve PlayKeys.ws

There's an error in the migration doc for including Play WS. Following the advice to enable the WS plugin by adding "libraryDependencies += PlayKeys.ws" to my build.sbt I get the following error

/...../build.sbt:22: error: value ws is not a member of object play.Play.autoImport.PlayKeys
Use webjars in samples: jquery and bootstrap
Use the same ObjectMapper by default in Java and Scala
Deregister only proxified drivers
Update JavaCache.md

correcting lag of dependency
Merge pull request #2794 from cchantep/dbplugin-dereg

DBPlugin deregisters all SQL Drivers from DriverManager
Merge pull request #2931 from Warry/use-webjars

Use webjars in samples: jquery and bootstrap
Merge pull request #2930 from GitsMcGee/master

Can't resolve PlayKeys.ws
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
Upgraded to javassist 0.18.2-GA

Fixes #1966
Merge pull request #2921 from muuki88/master

Upgrading sbt-native-packager and docs
Merge pull request #1966 from jroper/1966-upgrade-javassist

[Play-2.2.x] some code causes java.lang.VerifyError at runtime