Internal: moving to GitHub Actions for CI/CD

No change in functionality, but making sure that everything works using GitHub Action for continuous integration (CI) and deployment (CD)

Moving to new command-line argument handling

Merge pull request #16 from molssi-seamm/option-handling

Updated for the new command-line argument handling

Adding citations.

Merge pull request #15 from molssi-seamm/citations

Adding citations using new framework for them

Updated to work with the new system definition.

Merge pull request #12 from molssi-seamm/system

Moved to the new system.

Fixed bugs with edit dialog.

Merge pull request #11 from molssi-seamm/openkim

Added check in forcefield section for OpenKIM

Added plotting capabilities.

Consolidating a number of changes, but the noticeable user visible change is the addition of Plotly plots, which are currently used in LAMMPS.

End of 2019

This release contains the fixes for the "Cancel" button problem, wherein clicking Cancel did not update the GUI.

Running version with reasonable output

Merge pull request #5 from molssi-seamm/cleanup/description

Cleanup/description