Add 1.3 URLify solution

Author: rroque98

JavaScript/chapter01/1.3 - URLify/rroque98_sol.js

@@ -0,0 +1,8 @@
+// Write a method to replace all spaces within a string with '%20'
+
+const URLify = (string) => string.split(' ').join('%20');
+
+// Tests:
+console.log(URLify('Hello World') === 'Hello%20World');
+console.log(URLify('') === '');
+console.log(URLify('This is an example') === 'This%20is%20an%20example');