Don't tell pip to use mirrors anymore

The mirrors don't add any value now that pypi has a really good CDN
Merge pull request #397 from alex/patch-4

Don't tell pip to use mirrors anymore
SSHConfig.get_hostnames: List literal hostnames from SSH config
Changelog re #167
Merge branch 'master' into switch-to-cryptography
80-col tweaks
Changelog re #399
Use keyword arguments for arguments when creating a Transport.

Fixes #399
Cut 1.15.1
Merge branch '1.15'

Conflicts:
	sites/www/changelog.rst
Merge branch 'master' into switch-to-cryptography
Bump version numbers