Add readme to utils folder

Author: dodyg

projects/utils/README.md

@@ -0,0 +1,13 @@
+# Utils
+
+-   [Status Codes](http-status-codes)
+
+    Here we contrast between the usage of `Microsoft.AspNetCore.Http.StatusCodes` and `System.Net.HttpStatusCode`.
+
+-   [MediaTypeNames](media-type-names)
+
+    This class provides convenient constants for some common MIME types. It's not extensive by any means however `MediaTypeNames.Text.Html` and `MediaTypeNames.Application.Json` come handy.
+
+-   [MediaTypeNames - 2](media-type-names-2)
+
+    Using `FileExtensionContentTypeProvider` to obtain the correct MIME type of a filename extension.