1.0.0

• Move to using async requests instead of future executors.
• Adds cbz/zip using the new --save-as option. Resolves #1
• dest proprely behaves as if no value was provided. Resolves #11
• Adds pdf as a --save-as option. Resolves #27
• Image extension is properly saved and not hardcoded to jpg. Resolves #8
• Much faster downloading than before.

Full Changelog: v0.8.0...1.0.0