Pymol.cmd.read_pdbstr is missing "oname" attribue

**Describe the bug**
Line 40 in visualize.py is missing "oname" attribute resulting in:

`TypeError: read_pdbstr() missing 1 required positional argument: 'oname'`

**To Reproduce**
Just run `test/test_visualization.py`.

**Plip Version
Latest version from the `development` branch.
