Add tasks for all the new languages

Task/Copy-a-string/EchoLisp/copy-a-string.echolisp

@@ -0,0 +1,6 @@
+(define-syntax-rule (string-copy s) (string-append s)) ;; copy = append nothing
+    → #syntax:string-copy
+(define s "abc")
+(define t (string-copy s))
+    t → "abc"
+(eq? s t) → #t ;; same reference, same object