0.2.0

• removed dependency on jupyterlab 3
  • note: this doesn't mean it will "just work" with JupyterLab 4
• add basic syntax highlighting with @deathbeds/codemirror-pikchr
• vendor pikchr.wasm from fossil 2.20
• widget
  • rename dark to dark_mode
  • add css_class
• document
  • add toolbar with buttons for fit and tag
• mime
  • fallback text/html outputs get populated after rendering in the browser
  • metadata
    • rename dark to darkMode
    • add cssClass