Some users have changed their username

[benoit74]

While it seems impossible to do in the current UI, some users have changed their username. Probably mostly iFixit employees who got married. This causes issues because the old username is still used in links present in comments.

  The following links:
- ../../User/303268/mgrayjr
(User/303268/mgrayjr) were not found in article Tutoriel/Remplacement+du+disque+dur+de+l'iMac+21.5+"+EMC+2544/16729
  The following links:
- ../../User/104104/Optimus%20Goldberg
(User/104104/Optimus Goldberg) were not found in article Vue+Éclatée/Xbox+One+Teardown/19718
  The following links:
- ../../User/524640/Sam%20Lionheart
(User/524640/Sam Lionheart) were not found in article Tutoriel/Remplacement+de+l'antenne+Wi-Fi+de+l'iPhone+6/90315 
  The following links:
- ../../User/1536868/dgramatzki
(User/1536868/dgramatzki) were not found in article Tutoriel/Vue+éclatée+de+l'iMac+Pro/101807

I would suggest to either live with it or have a configuration map of known changes since they are quite limited for now.

[benoit74]

We can indeed keep in memory all user links that have been created and add redirect when needed once we process the user.