* Rename `eeprom_stm32` to `eeprom_legacy_emulated_flash`.
* Rename `flash_stm32` to `legacy_flash_ops`.
* Rename `eeprom_teensy` to `eeprom_kinetis_flexram`.
* Don't make EEPROM size assumptions with dynamic keymaps.
* Add support for checking against emulated flash, error out if someone attempts to build a board without specifying EEPROM size.
* Reorder defines so that MCU is considered last.
* Refactor EEPROM definitions for simplicity.
* Fix max sizing of kabedon/kabedon980.
* Fix max sizing of mechlovin/olly/jf.
* Fix unit tests.
* Review comments, add messages with values during build failures.