Rename exercises dir

Name it instead "topics" so it won't be
strange if some topics included "exercises" directory.

topics/aws/exercises/creating_records/exercise.md

@@ -0,0 +1,14 @@
+## AWS Route 53 - Creating Records
+
+### Requirements
+
+At least one registered domain
+
+### Objectives
+
+1. Create the following record for your domain:
+  1. Record name: foo
+  2. Record type: A
+  3. Set some IP in the value field
+
+2. Verify from the shell that you are able to use the record you've created to lookup for the IP address by using the domain name