0.5.3: Persistent viewport settings and import stations from CSV (+other changes)

0.5.3 adds support for persisting 3D viewport options between boots of OSC, which is handy if you have preferred visualization options that you typically always toggle on/off. It also adds support for importing stations into the mesh importer from a CSV (File > Import Stations from CSV in the mesh importer workflow), which is useful for importing (parts of) a muscle path into a mesh importer scene.

Change highlights:

• 3D viewport settings (e.g. muscle styling, show/hide the floor, background color) are now persisted between boots of OSC via a per-user configuration file (thanks @tgeijten, #782)
• The right-click step size menu for scalar property editors now includes suggestions for masses (it assumes the property is expressed in kilograms)
• Added Import Stations from CSV to the mesh importer's file menu, which provides a way of importing stations into the mesh importer scene from a CSV file (thanks @emmccain-uva, #149)
• Hovering over a recent or example osim file in the home screen now displays the full name of the file in a tooltip (thanks @AdrianHendrik, #784)
• Editors for component double properties (almost all scalar properties) now have - and + stepping buttons (previously: the steppers were only available for Vec3 properties; thanks @tgeijten, #781)
• The Show, Show Only This, and Hide buttons in the component context menu are now disabled if the clicked component, and all its children, have no Appearance property (#738)

See CHANGELOG.md for a full list of all changes.