(Emacs)+snippets from doom-snippet and removed default package

I've re-enabled yasnippet for ease of use, and added a ton of snippets
directly into my Dotfiles so only I get to curate what snippets are
removed.  Screw downloading them off someone else's repository at
their total mercy.

Emacs/.config/emacs/.config/yasnippet/snippets/rust-mode/cfg

@@ -0,0 +1,4 @@
+# -*- mode: snippet -*-
+# name: #[cfg(...)]
+# --
+#[cfg($0)]