improve go mod support (#46)

fix insert sort (#42)

add drone ci (#36)

* add drone ci

* add parallel piplines

* remove group

* remove comment

* remove comment

* remove wrong codecov config

* parallel drone

* remove parallel

* use matrix on drone

* drone add codecov

* circleci -> gitci.cn

Update Readme (#33)

* add more test cases & replace some err in errors.New(...) style & add some built-in err types

* update From & related test cases

* add test cases & fix bug

* fix issues

* update readme

add StringBuilder to improve performance and add ConvertPlaceHolder f…

…unction

add GroupBy/Having/OrderBy

Merge pull request #15 from go-xorm/lunny/add_test_in

add some tests for in and notin

Merge branch 'master' of https://github.com/go-xorm/builder