from the generated configuration at
https://rainboard.laas.fr/project/eigenpy/.gitlab-ci.yml

This:
- add the doc-coverage target, to save the generated documentation an
  code-coverage results
- add the format target, to check the code formatting (allow_failure is
  activated here for now), ref https://github.com/gepetto/linters
- set 18.04 as the main platform (for now, this affects only format &
  doc-coverage target)
- allow automatic retries in case of runner failures
- drop 14.04 checks

which is an obsolete PAL distribution

One hard disk drive is dead in our "eur0c" server. The RAID array needs
it to be replaced. eur0c is 2 months out of warranty. We already had this
budgetized, but Marchés Publics says we can only buy from one supplier,
and this supplier has 21 days delivery delays for this HDD.

Let's use another server instead.