v0.10.3: Big feature update! (music formats, save as pdf, other good stuff)

This updated ended up larger than expected, but I'm excited for these changes.

Music!

First is a feature I've wanted to add since starting: Rendering of sheetmusic and tabs from a (fairly) user friendly format.

Sheetmusic uses the ABC notation format, and is written inside a code block beginning with ```music or ```abc.

Guitar tabs and chords jTab, and are written in code blocks beginning with ```tab or ```guitar.

Both formats have basic code highlighting in JotDown's editor as well. See the markdown example file in Help > Show me an example for a couple of examples.

I'd like to add support for additional (non-6-string) instruments and tunings at some point, but probably not soon.

Save as PDF

The print button has been removed from the rendered preview display, and replaced with a save button which will save a new PDF for you instead.

Other Stuff

• You can now double click the different panel headings (Filters, Files, Outline) to quickly collapse or expand those sections, instead of having to drag them around.
• In dark mode, the editor is a little darker, and the text is a little brighter and more differentiated. I'm hoping to make this more customizable in the future (instead of just dark/light mode)
• More comfortable spacing around the editor panel
• The outline display will now scroll up and down to make sure the current section remains offscreen. Previously, the closest section was always highlighted, but wouldn't always be visible.
• JotDown has nicer (slightly thinner) scrollbars that blend in better and are less in the way.
• In distraction-free mode, the outline panel has a more subtle color scheme, and brightens on hover.
• Spellchecking is now disabled inside graph/diagram, music and tab code blocks.
• You can now exit distraction free mode by hitting escape twice quickly, in addition to the default shortcut (Shift + F11)