Globus-cli

Enhancements:

* Use the `cryptography` package instead of `M2Crypto` for the
`delegate-proxy` feature.
** Note: If you are using the `delegate-proxy` feature and
previously installed the CLI along with `M2Crypto`, you
will need to activate the CLI's virtualenv and install
the `cryptography` dependency:

source $HOME/.globus-cli-virtualenv/bin/activate
pip install globus-cli[delegate-proxy] --upgrade
deactivate

Enhancements:

* Add Delegate Proxy Activation to 'globus endpoint activate'
(requires M2Crypto for options to be displayed)
(https://github.com/globus/globus-cli/pull/306[306])
* Allow 'globus bookmark rename' and 'globus bookmark delete'
to accept either a bookmark name or id.
(https://github.com/globus/globus-cli/pull/292[292])
* Validate tokens upon login.
(https://github.com/globus/globus-cli/pull/286[286])
* Raise more helpful error messages on missing / invalid tokens.
(https://github.com/globus/globus-cli/pull/299[299])
* Display additional helptext with 'globus login'.
(https://github.com/globus/globus-cli/pull/289[289])
* Display additional fields with 'globus task show'.
(https://github.com/globus/globus-cli/pull/301[301])
* Make conflicting filters mutually exclusive in 'globus task event-list'
(https://github.com/globus/globus-cli/pull/294[294])

Bugfixes:

* Fix broken links in the docs.
(https://github.com/globus/globus-cli/pull/305[305])
* Update Six dependency to >=1.10.0 to meet SDK requirements.
(https://github.com/globus/globus-cli/pull/285[285])

* Initial release.