Add search condition
Merge branch 'master' into v2
Rename some interfaces
Update search.go
Make clone search conditions works
Move all chain method to main.go
Remove Chain.go
Move non-public DB method to private.go
Add Update, Updates back
Fix errors in field.go, model.go
Refact do.go
Refact do.go
Copy search when init do
Refact do
Should copy DB when save, update, delete
Better do.go
Yay, all tests passed