Restructure source and resource files (#46)

importantly, res is now res/res and css is now res/css

src/discord/relationship.cpp

@@ -0,0 +1,6 @@
+#include "relationship.hpp"
+
+void from_json(const nlohmann::json &j, RelationshipData &m) {
+    JS_D("type", m.Type);
+    JS_D("id", m.ID);
+}