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.

universe/data_structures_and_algorithms/find-duplicate-optimize-for-space.py

@@ -1,61 +0,0 @@
-from math import floor
-import unittest
-
-
-################################################################################
-# Solution
-################################################################################
-def bounds(r):
-    ct = len(r)
-    if ct % 2 == 0:
-        h = int(ct / 2)
-        return ct, h
-    else:
-        h = floor(ct / 2)
-        return ct, h
-
-
-def find_repeat(xs):
-    ct, h = bounds(xs)
-    rl = range(1, h + 1)
-    rr = range(h + 1, ct)
-    while True:
-        nl = len([None for x in xs if x in rl])
-        nr = len([None for x in xs if x in rr])
-        branch = rl if nl > nr else rr
-        if len(branch) == 1:
-            return branch[0]
-        ct, h = bounds(branch)
-        rl = range(branch[0], branch[0])
-        rr = range(branch[0] + h, branch[-1] + 1)
-    raise Exception(
-        'We could not find any duplicates in xs. Perhaps xs did not adhere to the usage contract.'
-    )
-
-
-################################################################################
-# Tests
-################################################################################
-class Test(unittest.TestCase):
-    def test_just_the_repeated_number(self):
-        actual = find_repeat([1, 1])
-        expected = 1
-        self.assertEqual(actual, expected)
-
-    def test_short_list(self):
-        actual = find_repeat([1, 2, 3, 2])
-        expected = 2
-        self.assertEqual(actual, expected)
-
-    def test_medium_list(self):
-        actual = find_repeat([1, 2, 5, 5, 5, 5])
-        expected = 5
-        self.assertEqual(actual, expected)
-
-    def test_long_list(self):
-        actual = find_repeat([4, 1, 4, 8, 3, 2, 7, 6, 5])
-        expected = 4
-        self.assertEqual(actual, expected)
-
-
-unittest.main(verbosity=2)