Obtain a compatible runtime from runconfig (#35)

TestRunner/Seq.fs

@@ -0,0 +1,22 @@
+namespace TestRunner
+
+[<RequireQualifiedAccess>]
+module internal Seq =
+
+    let tryMinBy (f : 'a -> 'b) (s : 'a seq) : 'a option =
+        use enum = s.GetEnumerator ()
+
+        if not (enum.MoveNext ()) then
+            None
+        else
+
+        let mutable answer = enum.Current
+        let mutable fAnswer = f enum.Current
+
+        while enum.MoveNext () do
+            let fNext = f enum.Current
+
+            if fNext < fAnswer then
+                answer <- enum.Current
+
+        Some answer