SPDX License Identifiers are a more compact / standardized
way of representing file license information.
See: https://spdx.dev/resources/use/#identifiers
This was done with the `ambr` search and replace tool.
ambr --no-parent-ignore --key-from-file --rep-from-file key.txt rep.txt *
If you double-click on a symlink to a directory while browsing with
a FilePicker, you most likely want to open the directory the symlink
points to, not open the symlink itself. So let's do that. :^)
This replaces the manual watch_file and Notifier handling with the new
Core::FileWatcher wrapper, which reduces the manual handling and makes
the code easier to reason about :^)
