Merge pull request #4487 from jingpei/datatypesDocUpdate

Update spelling in line 11 of sequelize/lib/data-types.js

lib/data-types.js

@@ -8,7 +8,7 @@ var util = require('util')
   , Validator = require('validator');
 
 /**
- * A convenience class holding commonly used data types. The datatypes are used when definining a new model using `Sequelize.define`, like this:
+ * A convenience class holding commonly used data types. The datatypes are used when defining a new model using `Sequelize.define`, like this:
  * ```js
  * sequelize.define('model', {
  *   column: DataTypes.INTEGER