maxux / ssh2-python

Updated sftp open documentation, example and readme for compatibility.
Resolves ParallelSSH#13.

Updated changelog

Enable embedded libssh2 builds by default.

Known host API implementation, tests and documentation.

Added OSX wheel builds for all OSX versions on Travis-CI.

 Updated manylinux wheel builds
    Updated osx wheel build

Update openssl wheel version

Direct tcpip test

Disable system package builds temporarily

Update travis OSX build.