Add a test for fix of issue #17098
merge with 3.3
Issue #17098: Be more stringent of setting __loader__ on early imported
modules. Also made test more rigorous.
Merge w/ 3.3 more fixes thanks to issue #17098
merge
merge
merge from 3.3
Issue #16256: OS X installer now sets correct permissions for doc directory.
Issue #16256: merge from 3.2
Issue #16256: merge from 3.3