2.3 release

[tflidd]

The release planning page could need an update:
https://github.com/owncloud/client/wiki/ReleaseDates

Judging from https://github.com/owncloud/client/milestones, there are already a few new features that might be worth testing with the testpilot-client. However would be great to know, when it enters beta phase and gets a feature-freeze. Especially when you manage to realize authentication via client-certificates 👍

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[guruz]

I tried to order issues in the milestone so ReadyToTest is sorted further down
https://github.com/owncloud/client/milestone/31
I also added more severities, gold tickets, assignees.

FYI The client SSL certificates branch has been merged, I'll check why the nightlies don't properly ypdate here.

I'll work to get a Change Log ready..

Still todo:

• @guruz have the Qt 5.6.1 build in the windows cross compile docker setup.
• @jturcotte improve overlay icon performance
• @SamuAlfageme try to test+close our ReadyToTest issues
• @ckamm and @ogoffart and @jturcotte finishing up current PRs, fix not-yet-working blue tickets, check current milestone.
• all: Check the open PRs and get them merged
• all: have a decision about chunking NG quality: Implement new Chunking Algorithm  #4019 (comment)

Time plan:
We want a beta in first half of January.
Then release beginning of february

FYI @ogoffart @jturcotte @ckamm @mrow4a @felixboehm @dschmidt @SamuAlfageme

[guruz]

Changelog.. 4ef7d04
Will be improved before release

[guruz]

-> #5519