Big cleanup and adding IdentityBuilder extensions the same way as the EF IdentityBuilder extensions do, allowing customer Identity setup.

src/GlobalVariables.cs

@@ -2,8 +2,14 @@
 
 namespace AspNetCore.Identity.MongoDbCore
 {
+    /// <summary>
+    /// A class holding global variables.
+    /// </summary>
     public static class GlobalVariables
     {
+        /// <summary>
+        /// A random number generator.
+        /// </summary>
         public static Random Random = new Random();
     }
 }