Polysh

* Fix infinite recursion in polysh entrance function

* Add basic (optional) sentry logging

* Python 3 fixes, code style fixes
* Fix crashes caused by decoding non UTF8 data received from remote shells
* Add patch with type hints

* Drop `:upload` and `:replicate` file transfer features
* Don't forward `Ctrl-Z` to the remote shells
* Save and restore history from `~/.polysh_hisory`
* Start supporting Python >= 3.4
* Stop supporting Python 2
* Add Travic CI testing

* Rename project to Polysh
* Add `--user` option to specify the remote user to login as
* New file transfer code that does not assume additional connectivity
between the host and the remote shells but still assumes connectivity
between the remote shells
* Add option to disable colorized hostnames

* If the `:{en|dis}able` command would have no effect, change all other
shells to the inverse enable value
* Consistently add a space between the shell name and the colon to ease
parsing the output
* Provide exit code aggregated from all remote shells by taking
the maximum
* Rename `:export_rank` to `:export_vars` as it now also exports
the hostname
* Add `--password-file` to login using a password
* Support `.zip` files on file transfer
* Switch from `setuptools` to `distutils`
* Color hostnames in the output