[Development] Gerrit Upgrade

[Frederik Gladhorn]

Hello,

We've been working on the Gerrit Upgrade for a while now and we are finally 
getting ready to deploy the new goodness.

We have all patches in our fork (yes, sadly we continue diverging a bit from 
mainstream, adding our own state handling for the CI).
The good news is that there are very few changes to Gerrit itself and most of 
the code is now in a self-contained plugin.

We aim to do the Upgrade to Gerrit 2.16.7 around the 20th of May (yes, that's 
a Monday, we assume Gerrit will be down for the full day that day).
The plan is to not actually take that long, but we want to make sure things 
actually work after the long wait and there are one or two things we cannot 
test very well without the right domain and everything in place.
Things look good though and I'm fairly confident that we'll manage the upgrade 
in May.

We will collect some documentation here, currently it's just a placeholder 
page, not yet worth visiting, unless you know the newer Gerrit and want to 
help out documenting what is new:
https://wiki.qt.io/Gerrit_Upgrade_2019

Cheers,
Frederik