Reorganize requires on top of files
Use Node.js util.inherits for inheritance
Split model test in more tests
Rename Connection.grex to client
Rename test/model.js to mogwai.js
Rename Client.createIndexes() to .initialize()
Add Model tests
Minor change to Mogwai.buildClient()
Connection constructor no longer takes any parameter
Move client.js to /client
Update gRex dependency to v0.5.2

- Fix 'No such property: type for class: Script3' issue.
- Add Model.save() test
Remove Model.exec(). More switch to gRex new API.
Synchronize model properties after insert()