fix #341 - work on flows instead of request/response internally.
simplify server changes for inline scripts
improve HTTPRequest syntax
fix some leftovers
Merge branch 'issue_341' into server_change_api

Conflicts:
	examples/redirect_requests.py
	libmproxy/console/common.py
Merge branch 'master' into issue_341
Merge branch 'issue_341' into server_change_api
coverage++
coverage++
much tests. so tcp. very wow.
change replay_request behaviour, refs #346; test upstream proxy mode
iframe injector example: use inline script
update docs, mostly revert 2f44b26b4cd014e03dd62a125d79af9b81663a93
streamline HTTPHandler.handle_flow()
fix race condition with the concurrent decorator
Merge branch 'master' into issue_341
Merge branch 'issue_341' into server_change_api
Merge pull request #342 from mitmproxy/server_change_api

Server change api
Merge pull request #347 from mitmproxy/issue_341

Remove BackReferenceMixin