Add tasks for all the new languages

Task/Semordnilap/EchoLisp/semordnilap.echolisp

@@ -0,0 +1,30 @@
+(lib 'struct)
+(lib 'sql)
+(lib 'words)
+
+(lib 'dico.fr.no-accent) ;; load dictionary
+(string-delimiter "")
+
+;; check reverse r of w is a word
+;; take only one pair : r < w
+(define (semordnilap? w)
+	    (define r (list->string (reverse (string->list w))))
+	    (and (word? r) (string<? r w)))
+	
+;; to get longest first
+(define (string-sort a b) (> (string-length a) (string-length b)))
+	
+(define (task)
+;; select unique words into the list 'mots'
+    (define mots (make-set (words-select #:any null 999999)))
+    (define semordnilap
+	    (list-sort string-sort (for/list ((w mots))
+	    #:when (semordnilap? w)
+	    w )))
+   (writeln 'pairs '→ (length semordnilap))
+   (writeln 'longest '→ (take semordnilap 5)))
+
+{{out}}
+(task)
+    pairs       →     345
+    longest     →     (rengager tresser strasse reveler retrace)