Full Changelog: 2.2...2.3

What's Changed

• Build vars by @jscrane in #30
• Menu items by @jscrane in #31
• add more variables from platform spec + bugfixes by @jscrane in #33
• processing menu-items automatically by @jscrane in #35
• Stm32 menus by @jscrane in #36
• Common upload target by @jscrane in #38
• update docs + attiny bugfix by @jscrane in #40

Full Changelog: 2.1...2.2

Tracking cores' updates: many small changes and improvements.

Complete rewrite using GNU make magic to parse boards.txt and platform.txt. This makes it much more tolerant of platform updates.

This is as far as I wanted to take this version of uC-Makefile