As suggested by Joshua, this commit adds the 2-clause BSD license as a
comment block to the top of every source file.
For the first pass, I've just added myself for simplicity. I encourage
everyone to add themselves as copyright holders of any file they've
added or modified in some significant way. If I've added myself in
error somewhere, feel free to replace it with the appropriate copyright
holder instead.
Going forward, all new source files should include a license header.
This fixes the bug seen in my monthly OS update video, where we'd look
through a stale copy of each file, instead of the potentially edited
version in the GTextDocument.
Search results are now also represented as a full GTextRange, and when
you jump to a search result, we select the whole matching range. :^)