New Features

Add support for making a font bold, italic, and bold/italic via the new .emphasis attribute. The cool thing about emphasis is that it can modify existing fonts, without having to re-specify the font. This means that you can do something like this: StringStyle(.font(.systemFont(ofSize: 17)), .emphasis(.italic)), and you'll get an italic version of the system font. Or, you can take any style and get the bold and/or italic version of it without knowing what its font is: someExistingStyle.byAdding(.emphasis([.bold, .italic])). Check out the example project for a cool use case for this in XML parsing! (@ZevEisenberg, #303 via #325)
Make Tracking's kerning(for:) method public. (@acacuce, #324)

Improvements