Fixed README 'Collections' ordering and re-exported diagram

Author: gridlocdev

README.md

@@ -19,10 +19,10 @@ This document contains a simplified list of concepts to guide new developers thr
   - [Conditionals](https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/statements/selection-statements)
   - [Methods](https://docs.microsoft.com/en-us/dotnet/csharp/methods)
   - [Collections](https://docs.microsoft.com/en-us/dotnet/csharp/programming-guide/concepts/collections)
-    - [Array](https://docs.microsoft.com/en-us/dotnet/csharp/programming-guide/arrays/)
     - [List](https://docs.microsoft.com/en-us/dotnet/api/system.collections.generic.list-1)
     - [Dictionary](https://docs.microsoft.com/en-us/dotnet/api/system.collections.generic.dictionary-2)
-  - [Iteration](https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/statements/iteration-statements)
+    - [Array](https://docs.microsoft.com/en-us/dotnet/csharp/programming-guide/arrays/)
+  - [Loops](https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/statements/iteration-statements)
   - [Namespaces](https://docs.microsoft.com/en-us/dotnet/csharp/fundamentals/types/namespaces)
   - [Using directives](https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/keywords/using-directive)
   - [String Interpolation](https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/tokens/interpolated)