Change-Id: I3b15ae34c0957a0f4026e1886c92a9770e9d170e

Change-Id: I5b174bba02856ede788dcb51ec9b0d598ea7d0df

* show highlights when replace empty line with content
* show inline diff when replace line with spaces with content

Authenticate or create users from OAuth providers

Refactor contributing process to make it more readable and make sure other core team members are mentioned.

Satellites for projects that were located in the root namespace needs to be recreated once they've been migrated to the creator’s namespace during the upgrade process.

This can be achieved by running the sudo -u git -H bundle exec rake gitlab:satellites:create RAILS_ENV=production during the update process.

The command has been added to the 5.4 to 6.0 update doc.

Since it is easily could break installations running on the server - hence the person doing the install should be able to make the decision to remove himself.