Add systemd.user.timers

(cherry picked from commit dcc93abe74d95b41c2fcfe74523da15efb7319a8)
Release date

(cherry picked from commit 5f2d5fcc12fb4d53dbb045671e2295d75e41cd74)
Release notes

(cherry picked from commit c502369a23244b9cd6b61733a14410c99a3d2701)
Drop reference to obsolete ControlGroupAttribute option

(cherry picked from commit adf62ba9c17285a498467e83a19243e52dfc36d3)
Create AMIs in the lb-nixos account

(cherry picked from commit 512d788a687180c4c354c60582c5bec0832bdc60)
Disambiguate util-linux package names

(cherry picked from commit 035e502b5b2dcf63efb191b49c1d8034ea203d6e)
Sort stuff

(cherry picked from commit 4df1ca0875ffa3f46be745ebff0c215600e3c3f6)
Release notes tweak

(cherry picked from commit cf1d9ed3178fefe816d6cf9b618573d896218345)
Document small channels

(cherry picked from commit 3370ee6a1322dfc353119c534c25a2c2861053c7)
blender: Add OpenCOLLADA support

(cherry picked from commit 49f53f63f5b5ae771822f05f80d150068cb57284)
pstack: Remove

It doesn't work anymore. And anyway, this probably shouldn't have been
a package in the first place (it's just some gdb options).

(cherry picked from commit 4a63787b78cd0cf20d343e4bbc31a3057d7876c8)