Added access to OpenEye mols and SMILES

• Added the ability to create a system from an OpenEye molecule and vice versa. This gives access to the OpenEye toolkit for generating conformers, etc.
• Added the ability to create a system from a SMILES string and create the SMILES string from a system using OpenEye.

Added units to properties in Openbabel molecules

• Any properties on the system and configuration are optionally added to the Openbabel Molecule object for e.g. writing to an SDF file. This adds the units of the properties explicitly

Bugfix: Incorrect coordinates from PubChem

• Fixed bug where the coordinates from PubChem were accidentally the 2-D rather than 3-D coordinates.

Bugfix: current configuration not updated properly

• Existing instances of systems did not correctly update when the default configuration was changed. This is release fixes the problem.

Bugfix: creating H2 from SMILES failed

• Fixed bug where creating molecules consisting of just hydrogen failed because RDKit by default ignores all hydrogens when reorienting the molecule.

Switching default for SMILES to RDKit rather than OpenBabel

• RDKit seems more robust, and also the atom typing uses RDkit, so compatibility is important.

Added more control over RDKit and OpenBabel creating systems

• Added control to from_RDKMol and from_OBMol to allow selectively updating the atoms, coordinates, and bonds

Rotated molecule from SMILES, InChI, or InChIKey to standard orientation

• Molecules created from line notation are created in an random orientation. This enhancement rotates them to the standard orientation, which will look nice for small, symmetric molecules.

Bugfix: bonds in RDKit

• There was an indexing bug translating bonds back from RDKit to SEAMM. The famous 0/1 problem!

Added gradients to atoms

• Added gradient on atoms as a separate table alongside atoms, so they take no space unless actually used.