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.

data_structures_and_algorithms/top-scores.py

@@ -0,0 +1,25 @@
+from collections import deque
+
+# list:
+# array:
+# vector:
+# bit-{array,vector}:
+
+
+def sort(xs, highest):
+    v = [0] * (highest + 1)
+    result = deque()
+
+    for x in xs:
+        v[x] += 1
+
+    for i, x in enumerate(v):
+        if x > 0:
+            result.appendleft(i)
+
+    return list(result)
+
+
+assert sort([37, 89, 41, 100, 65, 91, 53],
+            100) == [100, 91, 89, 65, 53, 41, 37]
+print("Tests pass!")