Add stubs for few exercises (#724)

* alphametics
* atbash-cipher
* binary-search
* bowling

exercises/alphametics/alphametics.js

@@ -0,0 +1,8 @@
+//
+// This is only a SKELETON file for the 'Alphametics' exercise. It's been provided as a
+// convenience to get you started writing code faster.
+//
+
+export const solve = () => {
+  throw new Error("Remove this statement and implement this function");
+};

exercises/atbash-cipher/atbash-cipher.js

@@ -0,0 +1,8 @@
+//
+// This is only a SKELETON file for the 'Atbash Cipher' exercise. It's been provided as a
+// convenience to get you started writing code faster.
+//
+
+export const encode = () => {
+  throw new Error("Remove this statement and implement this function");
+};

exercises/binary-search/binary-search.js

@@ -0,0 +1,18 @@
+//
+// This is only a SKELETON file for the 'Binary Search' exercise. It's been provided as a
+// convenience to get you started writing code faster.
+//
+
+export class BinarySearch {
+  constructor() {
+    throw new Error("Remove this statement and implement this function");
+  }
+
+  get array() {
+    throw new Error("Remove this statement and implement this function");
+  }
+
+  indexOf() {
+    throw new Error("Remove this statement and implement this function");
+  }
+}

exercises/bowling/bowling.js

@@ -0,0 +1,14 @@
+//
+// This is only a SKELETON file for the 'Bowling' exercise. It's been provided as a
+// convenience to get you started writing code faster.
+//
+
+export class Bowling {
+  roll() {
+    throw new Error("Remove this statement and implement this function");
+  }
+
+  score() {
+    throw new Error("Remove this statement and implement this function");
+  }
+}