Add "upply" (U-shaped apply, names are hard)

test.scm

@@ -64,6 +64,11 @@
     (define value (iterate 2 1+ 3))
     (assert-equal 5 value)))
 
+(define-test-suite "upply"
+  (define-test "test"
+    (define value (upply -3 5 = abs 1-))
+    (assert-equal #t value)))
+
 (define-test-suite "generator"
   (define-test "test"
     (define number-generator