Add the .gitignore file.
Merge branch 'master' of https://github.com/wewei/HyperModel
merge origin/master
Add implement object serializer

1. Implement object serializer
2. Remove the object pool from Model. We can have 2 objects with the
same id, they are considered equal, but not necessary to be 1 object.
Add serializeClosure method to model
Add deserializeClosure method to model.
Make serializeClosure support multi start objects
Add syntax sugar

Allow setup initializer/serializer/deserializer at property creation.