Made API models internal. Removed Discord.Net.API.

src/Discord.Net.Rest/API/Rest/ModifyMessageParams.cs

@@ -0,0 +1,14 @@
+#pragma warning disable CS1591
+using Newtonsoft.Json;
+
+namespace Discord.API.Rest
+{
+    [JsonObject(MemberSerialization = MemberSerialization.OptIn)]
+    internal class ModifyMessageParams
+    {
+        [JsonProperty("content")]
+        public Optional<string> Content { get; set; }
+        [JsonProperty("embed")]
+        public Optional<Embed> Embed { get; set; }
+    }
+}