SearchableBaseModel and 0.2.1-Beta

In 0.2.1, we've added a new model class -- gaeo.model.SearchableBaseModel. It directly inherits from gaeo.model.BaseModel and google.appengine.ext.search.SearchableModel. If your model is searchable (App Engine will help you construct the search indexes in each entity.), please create a model that extends SearchableBaseModel.

At the same time, we also release the 0.2.1 BETA version. The BaseModel.belongs_to and SearchableBaseMoel are included.