0.11.0-rc1

0.10.0 release candidate 04

0.10.0 release candidate 03

0.9.0 release candidate 02

fix left join bug, be compatible with sqlalchemy (apache#189)

merge to 4bd53476a7c3e6451aa1cf640a010d3b7bb0ec42

Merge code to github (apache#187)

* merge to 95787f8be1fd0ff215708fb0f49997b632876586
* Bugs fixed