capitalize constants, remove unnessesary usings

Author: ecrocombe

src/Linq2GraphQL.Client.Subscriptions/SSEClient.cs

@@ -1,4 +1,5 @@
 using System.Net.Http.Headers;
+using System.Net.Mime;
 using System.Reactive.Linq;
 using System.Reactive.Subjects;
 using System.Text;
@@ -34,7 +35,7 @@ public async Task Start()
 
         var request = new HttpRequestMessage(HttpMethod.Post, "")
         {
-            Content = new StringContent(json, Encoding.UTF8, "application/json")
+            Content = new StringContent(json, Encoding.UTF8, MediaTypeNames.Application.Json)
         };
 
         request.Headers.Accept.Add(new MediaTypeWithQualityHeaderValue("text/event-stream"));

src/Linq2GraphQL.Client.Subscriptions/SubscribeCommands.cs

@@ -2,7 +2,7 @@
 {
     internal class SubscribeCommands
     {
-        internal const string Subscribe = "subscribe";
-        internal const string Start = "start";
+        internal const string SUBSCRIBE = "subscribe";
+        internal const string START = "start";
     }
 }

src/Linq2GraphQL.Client.Subscriptions/SubscriptionProtocols.cs

@@ -1,14 +1,8 @@
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Text;
-using System.Threading.Tasks;
-
-namespace Linq2GraphQL.Client.Subscriptions
+namespace Linq2GraphQL.Client.Subscriptions
 {
     internal static class SubscriptionProtocols
     {
-        internal const string GraphQl_Transport_WS = "graphql-transport-ws";
-        internal const string GraphQl_WS = "graphql-ws";
+        internal const string GRAPGQL_TRANSPORT_WS = "graphql-transport-ws";
+        internal const string GRAPHQL_WS = "graphql-ws";
     }
 }

src/Linq2GraphQL.Client.Subscriptions/WSClient.cs

@@ -99,10 +99,10 @@ private string GetSubprotocolString()
         switch (_graphClient.SubscriptionProtocol)
         {
             case SubscriptionProtocol.GraphQLWebSocket:
-                return SubscriptionProtocols.GraphQl_Transport_WS;
+                return SubscriptionProtocols.GRAPGQL_TRANSPORT_WS;
 
             case SubscriptionProtocol.ApolloWebSocket:
-                return SubscriptionProtocols.GraphQl_WS;
+                return SubscriptionProtocols.GRAPHQL_WS;
 
             default:
                 throw new Exception($"{_graphClient.SubscriptionProtocol} is unknown");
@@ -114,10 +114,10 @@ private string GetSubscribeCommand()
         switch (_graphClient.SubscriptionProtocol)
         {
             case SubscriptionProtocol.GraphQLWebSocket:
-                return SubscribeCommands.Subscribe;
+                return SubscribeCommands.SUBSCRIBE;
 
             case SubscriptionProtocol.ApolloWebSocket:
-                return SubscribeCommands.Start;
+                return SubscribeCommands.START;
 
             default:
                 throw new Exception($"{_graphClient.SubscriptionProtocol} is unknown");

src/Linq2GraphQL.Client.Subscriptions/WebsocketRequestTypes.cs

@@ -1,10 +1,4 @@
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Text;
-using System.Threading.Tasks;
-
-namespace Linq2GraphQL.Client.Subscriptions
+namespace Linq2GraphQL.Client.Subscriptions
 {
     internal class WebsocketRequestTypes
     {