Add explicit dependency on commons-codec

Adding an explicit dependency on this was necessary after upgrading
`geoip2` to a version that didn't pull it in indirectly via Apache
HttpClient.

Author: oschwald

pom.xml

@@ -65,6 +65,11 @@
             <artifactId>geoip2</artifactId>
             <version>3.0.0</version>
         </dependency>
+        <dependency>
+            <groupId>commons-codec</groupId>
+            <artifactId>commons-codec</artifactId>
+            <version>1.15</version>
+        </dependency>
         <dependency>
             <groupId>commons-validator</groupId>
             <artifactId>commons-validator</artifactId>