Use PlayerDB.co for name lookups (#82)

I noticed that currently name lookups for UUIDs that are not cached, are
not supported in RedisBungee due to Mojang removing name history.

When looking at the usages, RedisBungee internally only uses the current
name (So no need for full name history), so I moved name lookups to
[PlayerDB](https://playerdb.co/), which does not have API rate limits
unlike Mojang's API.

closes #59

RedisBungee-Velocity/src/main/java/com/imaginarycode/minecraft/redisbungee/RedisBungeeVelocityPlugin.java

@@ -110,7 +110,7 @@ public class RedisBungeeVelocityPlugin implements RedisBungeePlugin<Player>, Con
         this.httpClient = new OkHttpClient();
         Dispatcher dispatcher = new Dispatcher(Executors.newFixedThreadPool(6));
         this.httpClient.setDispatcher(dispatcher);
-        //NameFetcher.setHttpClient(httpClient);
+        NameFetcher.setHttpClient(httpClient);
         UUIDFetcher.setHttpClient(httpClient);
     }