Integrated 0.8 will require Symfony 3.4
On Symfony 2.8 and 3.4, run the two tools mentioned on https://knpuniversity.com/screencast/symfony3-upgrade/deprecation-fixing-tools. Fix all deprecated code.
On Symfony 2.8 and 3.4, run unit tests and Behat tests to find deprecated warnings. Fix all deprecated code.
Move Symfony version to 3.4
Set up the new directory structure for the skeleton
Run unit tests and Behat tests again. Fix all errors.
Integrated 0.8 ships with Symfony 3.4. Follow the upgrade guides from Symfony when upgrading your code from Symfony 2.8 to 3.4:
Other changes are:
The Integrated bundles are combined in one repository. Load integrated/integrated as composer package
The view directories within Integrated are now lowercase (following the Symfony best practices)
For mongodb_options in parameters.yml you might need to replace "db" with "authSource" to specify the authentication database
Uglyfyjs is not required any more, becuase of future Webpack migration