- Added drop/add primary key methods to QueryBuilder.php
- Added mysql specific dropPrimarykey method
- Added sqlite specific dropPrimarykey and addPrimaryKey methods
- Added uint testing for dropPrimarykey and addPrimaryKey methods
- Corrected postgresql column types, by adding length and precision

Feature was requested in yiisoft/yii#765

- Better names
- Removed not used MySQLTestCase
- Moved base testcase for DB to db namespace
- Minor style fixes

Appended newlines to every PHP document that did not have a newline as the last character in the file.

finished Sort.

Added support for scopes defined in AR classes.

refactored Transaction.

finished AR documentation.