v1.9.0

Feature changes

• New source: https://comixextra.com! (#82, #80)
  • This source has some broken image links that Mandown may stumble over
• When an image link 404s, Mandown now continues and ignores it for the current chapter instead of crashing

Bug fixes

• Update Manganato to support their new domain (chapmanganato.com → chapmanganato.to)
• Improve error messages