Add 2.11 branch with support to install 2.11
Fix new repo (2.7-9 deprecated, add 2.10/2.11
Merge branch 'branches/rudder/2.6' into branches/rudder/2.10
Add 2.11
Merge branch 'branches/rudder/2.10' into branches/rudder/2.11
Fixes #5129: DEBIAN_FRONTEND=noninteractive
Merge branch 'branches/rudder/2.6' into branches/rudder/2.10
Merge branch 'branches/rudder/2.10' into branches/rudder/2.11
Merge branch 'branches/rudder/2.11'