Extract pysaltapi library into standalone lib

[saltstack]

Extract pysaltapi library into standalone lib

[whiteinge]

First stab at this is in dec388a.

Research keeping the lib and the CLI scripts in the same project but have build-time options to install the CLI scripts or not. Then upload to PyPI as two separate install-ables.

[jacksontj]

@whiteinge This might be better to create as a client library in salt-api? Or maybe to define THE salt-api and have a single client. As of today there isn't an official salt api (as far as a spec to implement against).

[whiteinge]

@jacksontj the idea behind this lib (and pepper) is to have a no-dep install. E.g., pip install salt-pepper, or just grab the libpepper.py file off GitHub, then be able to import pepper.libpepper from a custom script to talk to a remote salt-api install. So for that reason I'd like to keep this a separate project.

The current implementation calls out the rest_cherrypy module as the intended interface.

I've filed an issue to create a REST API spec here: saltstack/salt#13698. Pepper should be written to be able to use any interface that adheres to the spec. (Perhaps those tests should live in this repo, in fact!)