Rename dotfiles -> briefcase

Renaming my mono-repo briefcase.

I first introduced this commit in master, but it introduced a bug where one of
two things would happen:

1. Emacs wouldn't start and would crash X.
2. Emacs would start but my keyboard wouldn't work.

I learned some valuable debugging skills in the process. Here are some of them:

When my keyboard was broken, I wanted to control my computer using my
laptop. Thankfully this is possible by using `x2x`, which forward X events from
the SSH client to the SSH host.

```shell
> # I'm unsure if this is the *exact* command
> ssh -X desktop x2x -west :0.0
```

Git commit-local bisecting. I didn't need to do a `git bisect` because I knew
which commit introduced the bug; it was HEAD, master. But -- as you can see from
the size of this commit -- there are many changes involved. I wanted to binary
search through the changes, so I did the following workflow using `magit`:

- git reset --soft HEAD^
- git stash 1/2 of the files changed
- re-run `nix-env -f ~/briefcase/emacs -i`
- restart X session
- If the problem persists, the bug exists in the non-stashed files. Repeat the
  process until you find the bug.

In my case, the bug was pretty benign. Calling `(exwm/switch "Dotfiles")` at the
bottom of `window-manager.el` was failing because "Dotfiles" is the name of a
non-existent workspace; it should've been `(exwm/switch "Briefcase")`.

There may have been more problems. I changed a few other things along the way,
including exposing the env vars BRIEFCASE to `wpcarros-emacs` inside of
`emacs/default.nix`.

The important part is that this was a valuable learning opportunity, and I'm
glad that I'm walking away from the two days of "lost productivity" feeling
actually productive.

5 files changed, 6 insertions, 6 deletions

diff --git a/configs/install b/configs/install
index 4aedf35be1f7..c810dfd4f9f2 100755
--- a/configs/install
+++ b/configs/install
@@ -1,6 +1,6 @@
 #!/usr/bin/env bash
 
-configs="$DOTFILES/configs"
+configs="$BRIEFCASE/configs"
 
 case $(hostname) in
   $DESKTOP)
diff --git a/configs/shared/.config/fish/config.fish b/configs/shared/.config/fish/config.fish
index 754470618c1f..20de7a7f78cc 100644
--- a/configs/shared/.config/fish/config.fish
+++ b/configs/shared/.config/fish/config.fish
@@ -286,7 +286,7 @@ abbr --add ef e ~/functions.zsh
 abbr --add el e ~/variables.zsh
 abbr --add ex e ~/.Xresources
 abbr --add em e ~/.tmux.conf
-abbr --add er e ~/Dropbox/dotfiles/README.md
+abbr --add er e $BRIEFCASE/README.md
 
 # Couple the s* aliases to the <leader>s* kbds in vim.
 abbr --add sz source ~/.zshrc
diff --git a/configs/shared/.config/lf/marks b/configs/shared/.config/lf/marks
index 295576a0da1a..4aff94c32f19 100644
--- a/configs/shared/.config/lf/marks
+++ b/configs/shared/.config/lf/marks
@@ -1,6 +1,6 @@
 D:~/Dropbox
 G:/usr/local/google/home/wpcarro/Downloads
 M:/usr/local/google/home/wpcarro/Downloads
-c:~/dotfiles/configs
-d:~/dotfiles
+c:~/briefcase/configs
+d:~/briefcase
 s:~/Pictures/screenshots
diff --git a/configs/shared/.profile b/configs/shared/.profile
index 6513c2c9b5c0..30b9804699e7 100644
--- a/configs/shared/.profile
+++ b/configs/shared/.profile
@@ -52,7 +52,7 @@ LOCALE_ARCHIVE=$(readlink ~/.nix-profile/lib/locale)/locale-archive
 export LOCALE_ARCHIVE
 
 # Set environment variables for Nix. Don't run this for systems running NixOS.
-# TODO: Learn why I can't use the variables from ~/dotfiles/.envrc.
+# TODO: Learn why I can't use the variables from ~/briefcase/.envrc.
 case $(hostname) in
   zeno.lon.corp.google.com) . ~/.nix-profile/etc/profile.d/nix.sh;;
   seneca) . ~/.nix-profile/etc/profile.d/nix.sh;;
diff --git a/configs/uninstall b/configs/uninstall
index 526c32113f53..7151843d6070 100755
--- a/configs/uninstall
+++ b/configs/uninstall
@@ -1,6 +1,6 @@
 #!/usr/bin/env bash
 
-configs="$DOTFILES/configs"
+configs="$BRIEFCASE/configs"
 
 case $(hostname) in
   $DESKTOP)