Update README
Update README with some instructions to windows users
Removed mistaken piece of code, this is responsibility of findById()
Refactor and added some tests
Separated model core to the model api, closes #7
Added instructions to write tests
Added some comments
Added find automatic methods for custom fields e for default fields: id, author, category, status and date
Removed findById method
Added test in case of access a method that doesn't exists
Merge remote-tracking branch 'alter/master'