use filesource object for loading all http stuff

src/util/filesource.cpp

@@ -0,0 +1,27 @@
+#include <mbgl/util/filesource.hpp>
+#include <mbgl/platform/platform.hpp>
+
+namespace mbgl {
+
+FileSource::FileSource(const std::shared_ptr<uv::loop> &loop)
+    : loop(loop) {}
+
+
+void FileSource::setBase(const std::string &value) {
+    base = value;
+}
+
+const std::string &FileSource::getBase() const {
+    return base;
+}
+
+void FileSource::load(ResourceType type, const std::string &url, std::function<void(platform::Response *)> callback) {
+    // convert relative URLs to absolute URLs
+
+    // try to load from disk (not yet)
+
+    // load from the internet
+    platform::request_http(url, callback, loop);
+}
+
+}