Added folder batch example

examples/batch/folder.lisp

@@ -0,0 +1,24 @@
+; open every file in a folder.
+(defn filter-jpg 
+  (file-name) 
+  (eq 
+    (last 
+      (split file-name ".")) "jpg"))
+;
+(def images 
+  (filter 
+    (dir) filter-jpg))
+;
+(debug 
+  (concat "Found: " 
+    (len images)))
+;
+(defn image-operation 
+  (file-name) 
+  (
+    (def file-path 
+      (concat 
+        (dirpath) "/" file-name)) 
+    (open file-path)))
+;
+(each images image-operation)