Method pref (ParallelSSH#140)

* Added new libssh2 1.9.0 error codes as exceptions.
* Added session method and supported algorithm functions - resolves ParallelSSH#128
* Updated changelog
* Updated documentation

Updated documentation (ParallelSSH#139)

Sftp attrs (ParallelSSH#124)

* Minor fixes for kdb int
* Added SFTP attribute flags. Updated sftp tests - resolves ParallelSSH#119
* Updated change log

Circleci (ParallelSSH#116)

* Added circleci config. Updated travis cfg

Manifest (ParallelSSH#115)

* Updated travis cfg
* Updated manifest

Readline (ParallelSSH#111)

* Added line parsing to utils. Added utils line parsing tests.
* Updated changelog.

Fix manylinux build (ParallelSSH#106)

Fix linux wheel build versioning information.

New release (ParallelSSH#68)

Disabled OSX 10.11 wheel builds
Updated travis cfg for osx builds
Removed system package builds. Updated travis cfg to not login or push to docker on PR builds.
Switched testing to pytest.
Removed channel close on channel object de-allocation. Removed GIL release on session and channel object de-allocation. Updated Changelog.
Removed out of repo package files before building wheels and updated gitignore - resolves ParallelSSH#14
Migrated manylinux wheel builds to openssl 1.1.
Migrated Windows builds to openssl 1.1.
Updated changelog. Updated manylinux wheel embedded libssh2 version.

Updated appveyor cfg. Added openssl and zlib static archives for wind…

…ows builds.