Add documentation

library/gensym.yap

@@ -1,8 +1,28 @@
+/**
+ * @file   gensym.yap
+ * @author VITOR SANTOS COSTA <vsc@VITORs-MBP.lan>
+ * @date   Tue Nov 17 18:37:13 2015
+ * 
+ * @brief  Generate a new atom.
+ * 
+ * 
+*/
 :- module(gensym, [
 	gensym/2,
 	reset_gensym/1,
 	reset_gensym/0
-    ]).
+                  ]).
+
+/**
+* @defgroup gensym Generate a new symbol.
+* @ingroup library
+*
+* Predicates to create new atoms based on the prefix _Atom_.
+* They use a counter, stored as a
+* dynamic predicate, to construct the atom's suffix. 
+*
+*/
+
 
 :- dynamic gensym_key/2.