Fixed send_from_directory not rebasing to the root path.  This fixes #921
Added a test for sending from directories
Fixed PyStringIO in tests for 2.x
Closed an unclosed file in the tests
Merge branch '0.10-maintenance'
Merge branch 'master' of github.com:mitsuhiko/flask
fix issue #879 and add a test for it

Signed-off-by: Armin Ronacher <armin.ronacher@active-4.com>
Use a condition variable instead of sleeping
Documented fix for #879
Merge branch '0.10-maintenance'