0.7.0

• Lots of under-the-hood improvements to syntax highlighting, as well as:
  • replaced Oniguruma regex dependency with Rust-based fancy-regex
  • better error handling
• Improved terminal renderer error handling
• Cursor types now change based on mode
• Added ability to build amp using Nix
• Added Wayland clipboard support
• Updated to build using Rust 2021 edition
• Added ability to reflow text based on line length guide
• Improved unicode support when adding trailing newline
• Added ability to configure syntax overrides based on file extension
• Added ability to comment out a selection of text
• Improved handling of very small terminal sizes
• Updated to correctly restore terminal contents after quitting