Welcome Pierre-Yves as a backup release manager (thus new GPG signature)

[Raphaël Gomès]

Hi all,

The next two releases, 6.8.1 today and 6.8.2 around the 1st of September 
barring any emergency releases will be done by Pierre-Yves (CC'd). The 
first one to see if all is setup correctly on his side, the second one 
because I'll be in vacation.

His GPG signature is ED213E486B23249BDC107B5945CAA92A71CA027B with email 
pierre-yves.david at ens-lyon.org.

Thanks,
Raphaël