workaround missing _tunnel_host attr in python 2.6

Adds the same workaround as on line 175, which allows this lib to work on python2.6
Fix typo
Merge pull request #381 from yamaneko1212/master

Fix typo
Update connection.py

Removed unnecessary check for _tunnel_host
Merge pull request #380 from Shootfast/patch-1

workaround missing _tunnel_host attr in python 2.6.
CPython 3.4 is a thing
Merge pull request #382 from t-8ch/support_py34

CPython 3.4 is a thing.
Make sure we verify against the correct host.

For context on this change, check issue #385 on GitHub.
Merge pull request #385 from Lukasa/341

TLS Verification will break in Python 3.4.1 when using a Proxy
CHANGES for #385
Some wording and style fixen for #385.

I'm going to regret editing this in the web UI and not sending a PR, aren't I...
fix docs copy/paste typo
Merge pull request #389 from jschneier/master

fix skip test copy/paste typo
refactor ssl tests
Merge pull request #390 from jschneier/refactor-ssl-tests

refactor ssl tests
Test proxy behavior when origin server disconnects

Add a test for a CONNECT proxy where the remote server closes the
connection, and then we try to reuse it.
make sure we send connection: close header (should probably consider testing
all 3 ways connection might close)
Fix reconnecting, through a proxy, to a closed connection
treat closed connections as dropped
Since appengine (and possibly other) environments may not have
the conn.auto_open attribute, don't rely on its presence (use getattr to read
it).
document the util module again
add disable_cache to make_headers
Merge pull request #396 from jschneier/docs_fixup

document the util module again