added global drop method

lib/sequelize/sequelize.js

@@ -66,9 +66,23 @@ var instanceMethods = {
         .on('failure', function(err) { eventEmitter.emit('failure', err) })
         .on('failure', function(err) { eventEmitter.emit('failure', err) })
     })
     })
     return eventEmitter.run()
     return eventEmitter.run()
+  },
+
+  drop: function() {
+    var self = this
+
+    return new Utils.CustomEventEmitter(function(emitter) {
+      var chainer = new Utils.QueryChainer
+
+      self.modelManager.models.forEach(function(model) { chainer.add(model.drop()) })
+
+      chainer
+        .run()
+        .on('success', function() { emitter.emit('success', null) })
+        .on('failure', function(err) { emitter.emit('failure', err) })
+    }).run()
   }
   }
 }
 }
 
 
-
 Sequelize.Utils._.map(DataTypes, function(sql, accessor) { Sequelize[accessor] = sql})
 Sequelize.Utils._.map(DataTypes, function(sql, accessor) { Sequelize[accessor] = sql})
 Sequelize.Utils._.map(instanceMethods, function(fct, name) { Sequelize.prototype[name] = fct})
 Sequelize.Utils._.map(instanceMethods, function(fct, name) { Sequelize.prototype[name] = fct})