Prepare for version 1.1

[Add]
- add columns method.
- change column method.
- remove column method.
- finishing unique syntax.
- Multi-condition.
[Changes]
- Changes the constructor for Condition to be compatible with the
multiCondition.
[Remove and improved]
- Remove AlterType class (Don't need this)
- Improved a lit bit the code when a error happened. ApiResponse should
be an error.