1.4.0rc1

pypylon release 1.4.0rc1

Changes:
- Fixed a regression introduced in version 1.1.0 where pypylon stopped being
  importable when used in an application built with PyInstaller.
- Fixed PylonImageBase so that the methods CanSaveWithoutConversion, Save
  and Load can be used. Added a sample that shows how images can be saved.
- Added macOS platform support
- Switched to Pylon 5.2.0 for windows and linux builds