Save machine ident in captures and compare to machine ident on open

* If the machine idents differ in significant ways that we'd consider
  it to be a different platform (currently just OS), and if so mark it
  as supported but suggested to be replayed remotely.

renderdocui/Interop/Enums.cs

@@ -504,6 +504,13 @@ namespace renderdoc
         Percentage,
     };
 
+    public enum ReplaySupport
+    {
+        Unsupported,
+        Supported,
+        SuggestRemote,
+    };
+
     public enum ReplayCreateStatus
     {
         Success = 0,