Version 0.5.0

Added

• Support for ATtiny404 (#111 by @agausmann).
• Support for the critical-section crate via a critical-section-impl feature flag (#116).

Changed

• Patched registers for ATmega8 (#112 by @Rutherther).
• Upgraded to svd2rust 0.28. This changes the register API slightly, please check upstream docs for details (#118).

And finally some misc documentation fixes and improvements in #110 by @mbuesch. Thanks everyone for the help!