9.0.0

• Added new boards:
  • Olimex STM32-H103
  • Waveshare Open103Z
• Updated Zephyr framework to v2.4.0 (release notes)
• Updated Arduino MXChip core to v2.0.0 (release notes)
• Minor bugfixes and improvements

Breaking Zephyr API changes

Zephyr v2.4 deprecates Zephyr integer types in favor of C99 integer types. More information about other API changes can be found here.