Release of version 1.5.11

[WeisLeDocto]

This PR merges the 1.5.11 branch into master.

It contains :

• An improvement in the layout of the Grapher Block
• Fixes for several bugs in the build process
• Fixes in the distributed examples
• The addition of warnings signaling the features that will be deprecated in version 2.0.0

This release is the very last one before version 2.0.0 ! It contains almost no improvements compared to version 1.5.10, and should be used for preparing a migration to version 2.0.0 using the warnings.

Closes #59