Document mem-fs-editor in API doc, also remove references to src/dest…

… object

Fix #727

lib/base.js

@@ -48,21 +48,20 @@ var fileLogger = { write: _.noop, warn: _.noop };
  * @param {String|Array} args
  * @param {Object} options
  *
- * @property {Object}  env         - the current Environment being run
- * @property {Object}  args        - Provide arguments at initialization
- * @property {String}  resolved    - the path to the current generator
- * @property {String}  description - Used in `--help` output
- * @property {String}  appname     - The application name
- * @property {Storage} config      - `.yo-rc` config file manager
- * @property {Object}  src         - File util instance scoped to `sourceRoot`
- * @property {Object}  dest        - File util instance scoped to `destinationRoot`
- * @property {Function} log       - Output content through Interface Adapter
+ * @property {Object}   env         - the current Environment being run
+ * @property {Object}   args        - Provide arguments at initialization
+ * @property {String}   resolved    - the path to the current generator
+ * @property {String}   description - Used in `--help` output
+ * @property {String}   appname     - The application name
+ * @property {Storage}  config      - `.yo-rc` config file manager
+ * @property {Object}   fs          - An instance of {@link https://github.com/SBoudrias/mem-fs-editor Mem-fs-editor}
+ * @property {Function} log         - Output content through Interface Adapter
  *
  * @example
- * var yeoman = require('yeoman-generator');
- * var MyGenerator = yeoman.generators.Base.extend({
- *   createGruntfile: function() {
- *     this.dest.write('// Grunt file content', 'Gruntfile.js');
+ * var generator = require('yeoman-generator');
+ * var MyGenerator = generator.Base.extend({
+ *   writing: function() {
+ *     this.fs.write('var foo = 1;', this.destinationPath('index.js'));
  *   }
  * });
  */