Splice ./universe directory into ./

Manually merging:
- README.md: I added the description from universe/README.md into the heading of
  dotfiles/README.md.
- .envrc: dotfiles/.envrc was a superset of universe/.envrc
- .gitignore: Adding some of the ignored patterns from universe/.gitignore to
  dotfiles/.gitignore

Everything else here should be a simple rename.

lisp/prelude.lisp

@@ -0,0 +1,14 @@
+(in-package #:cl-user)
+(defpackage #:prelude
+  (:documentation "Supporting miscellaneous utility functions and macros.")
+  (:use #:cl)
+  (:shadow #:type)
+  (:export #:type #:comment))
+(in-package #:prelude)
+
+;; TODO: Add documentation to these macros.
+
+(defmacro type (name in out)
+  `(declaim (ftype (function ,in ,out) ,name)))
+
+(defmacro comment (&rest _forms) nil)