add support to redirect to another URL and dispatch it again.
test the redirect feature.
use another handler for user-created redirecting to fix up the test.
update the api document.
refactor the http_client into pipeline property.
fix up the options of http_client.
fix up the broken unittest for last commit.
remove the magic arguments of http_client.
fix up the unicode error for incoming non-ascii query.
get the version from __init__ without importing.
expose the most common of objects into top namespace.
update the importing usage in the tests.
rename the class 'BrownAnt' into 'Brownant'.
test the deprecation class.