Release X.Y (202?-??-??)

Commands which take installables on the command line can now read them from the standard input if passed the --stdin flag. This is primarily useful when you have a large amount of paths which exceed the OS arg limit.
The special handling of an installable with .drv suffix being interpreted as all of the given store derivation's output paths is removed, and instead taken as the literal store path that it represents.

The new ^ syntax for store paths introduced in Nix 2.13 allows explicitly referencing output paths of a derivation. Using this is better and more clear than relying on the now-removed .drv special handling.

For example,
```
$ nix path-info /nix/store/gzaflydcr6sb3567hap9q6srzx8ggdgg-glibc-2.33-78.drv
```
now gives info about the derivation itself, while
```
$ nix path-info /nix/store/gzaflydcr6sb3567hap9q6srzx8ggdgg-glibc-2.33-78.drv^*
```
provides information about each of its outputs.