Sasctl

-------------------
**Improvements**
- `PagedList` handles situations where the server over-estimates the number of items available for paging.
- The version of SAS Viya on the server can now be determined using `sasctl.platform_version()`.

**Bugfixes**
- Reworked the `model_repository.get_repository()` to prevent HTTP 403 errors that could occur with some Viya environments.

-------------------
**Bugfixes***
- Fixed an issue with JSON parsing that caused the `publish_model` task to fail with Viya 4.0.

------------------
**Improvements**
- Added the `as_swat` method to the `Session` object, allowing connection to CAS through SWAT without an additional authentication step.

**Changes**
- Integrated PZMM into `Session` calls and removed redundant function calls in PZMM.
- ROC and Lift statistic JSON files created by PZMM are now generated through CAS actionset calls.
- Updated the PZMM example notebook, `FleetMaintenance.ipynb`, to include integration of PZMM with sasctl functions.

**Bugfixes**
- Reworked the `model_repository.get_repository()` to prevent HTTP 403 errors that could occur with some Viya environments.

------------------
**Bugfixes**
- Added PZMM fitstat JSON file to manifest.

-------------------
**Improvements**
- PZMM module moved from a stand-alone [repository](https://github.com/sassoftware/open-model-manager-resources/tree/master/addons/picklezip-mm) to a sasctl submodule.
- Introduced deprecation warnings for Python 2 users.

----------------
**Bugfixes**
- Fixed PyMAS utilities to correctly work functions not bound to pickled objects.
- Model target variables should no longer appear as an input variable when registering ASTORE models.