The `kdepim-addons` dependency is needed in KMail to add many of the
standard plug-ins, including the "External Editor" plug-in.

birdtray crashes not finding the translations without this fix

Both functions expect oh-my-zsh to be in ~/.oh-my-zsh and try to
modify the directory. This doesn't work, since it is in the
Nix store.

This is required by (among others) Podman to run containers in rootless mode.

Other distributions such as Fedora and Ubuntu already set up these mappings.

The scheme with a start UID/GID offset starting at 100000 and increasing in 65536 increments is copied from Fedora.

…appings

According to the README of batinfo, it runs only on Linux-based operating systems.

bovo: init at 19.12.3

picmi: init at 19.12.3

https://github.com/imsnif/bandwhich/releases/tag/0.16.0

gerrit: 3.1.5 -> 3.2.2

oh-my-zsh: undefine functions that don't work on Nix

batinfo: limit build to Linux

kmail: add missing dependency (kdepim-addons)

https://github.com/busyloop/lolcat/releases/tag/v100.0.1

birdtray: fix qttranslations path

lolcat: 100.0.0 -> 100.0.1

nixos.users-groups: Set up subuid/subgid mappings for all normal users

```
    Add the installation prefix of "Qt5Core" to CMAKE_PREFIX_PATH or set
    "Qt5Core_DIR" to a directory containing one of the above files.  If
    "Qt5Core" provides a separate development package or SDK, be sure it has
    been installed.
```