http api/service: map .js to application/json and use in http clients

This is to trick the CDN into caching responses

http-api/src/main/java/net/runelite/http/api/feed/FeedClient.java

@@ -42,7 +42,7 @@ public class FeedClient
 	public FeedResult lookupFeed() throws IOException
 	{
 		HttpUrl url = RuneLiteAPI.getApiBase().newBuilder()
-			.addPathSegment("feed")
+			.addPathSegment("feed.js")
 			.build();
 
 		logger.debug("Built URI: {}", url);

http-api/src/main/java/net/runelite/http/api/item/ItemClient.java

@@ -174,7 +174,7 @@ public class ItemClient
 	{
 		HttpUrl.Builder urlBuilder = RuneLiteAPI.getApiBase().newBuilder()
 			.addPathSegment("item")
-			.addPathSegment("prices");
+			.addPathSegment("prices.js");
 
 		HttpUrl url = urlBuilder.build();
 

http-api/src/main/java/net/runelite/http/api/worlds/WorldClient.java

@@ -44,7 +44,7 @@ public class WorldClient
 	public WorldResult lookupWorlds() throws IOException
 	{
 		HttpUrl url = RuneLiteAPI.getApiBase().newBuilder()
-			.addPathSegment("worlds")
+			.addPathSegment("worlds.js")
 			.build();
 
 		logger.debug("Built URI: {}", url);

http-service/src/main/java/net/runelite/http/service/SpringContentNegotiationConfigurer.java

@@ -0,0 +1,45 @@
+/*
+ * Copyright (c) 2018, Adam <Adam@sigterm.info>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package net.runelite.http.service;
+
+import org.springframework.context.annotation.Configuration;
+import org.springframework.http.MediaType;
+import org.springframework.web.servlet.config.annotation.ContentNegotiationConfigurer;
+import org.springframework.web.servlet.config.annotation.EnableWebMvc;
+import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
+
+/**
+ * Configure .js as application/json to trick Cloudflare into caching json responses
+ */
+@Configuration
+@EnableWebMvc
+public class SpringContentNegotiationConfigurer extends WebMvcConfigurerAdapter
+{
+	@Override
+	public void configureContentNegotiation(ContentNegotiationConfigurer configurer)
+	{
+		configurer.mediaType("js", MediaType.APPLICATION_JSON);
+	}
+}