merge: Add binary to decimal test file and convert function to es6 model. (#806)

* Added Hex to Binary conversion

* Add Binary to decimal test

* Fix Style

Conversions/HexToBinary.js

@@ -0,0 +1,37 @@
+const binLookup = (c) => {
+  switch (c.toLowerCase()) {
+    case '0': return '0000'
+    case '1': return '0001'
+    case '2': return '0010'
+    case '3': return '0011'
+    case '4': return '0100'
+    case '5': return '0101'
+    case '6': return '0110'
+    case '7': return '0111'
+    case '8': return '1000'
+    case '9': return '1001'
+    case 'a': return '1010'
+    case 'b': return '1011'
+    case 'c': return '1100'
+    case 'd': return '1101'
+    case 'e': return '1110'
+    case 'f': return '1111'
+    default: return ''
+  }
+}
+const hexToBinary = (hexString) => {
+  /*
+    Function for convertung Hex to Binary
+
+    1. We convert every hexadecimal bit to 4 binary bits
+    2. Conversion goes by searching in the lookup table
+
+    */
+
+  let result = ''
+  hexString = hexString.split('')
+  hexString.forEach(c => { result += binLookup(c) })
+  return result
+}
+
+export default hexToBinary