Test migration to jest by hand

Apparently using regular expressions is way easier.

test/sumPower/sumPower.js

@@ -0,0 +1,6 @@
+const sumPower = (end, power = 2, start = 1) =>
+Array(end + 1 - start)
+.fill(0)
+.map((x, i) => (i + start) ** power)
+.reduce((a, b) => a + b, 0);
+module.exports = sumPower;