* Get UBL Mesh Generation, Mesh Save & Mesh Load working with 32-Bit platforms
* clean up read_data() and write_data() for non-LPC1768 HAL's
* Get read_data() and write_data() return codes consistent
All HAL's read_data() and write_data() return false if they succeed.
* Get read_data() and write_data() return codes to be consistent
Make read_data() and write_data() return true if an error happens.
* Say UBL is now checked out on machine types in default Configuration.h file.
Adding files for STM32F1 HAL based on libmaple/stm32duino core.
Current persistent_store uses cardreader changes to be sent in separate
commit, but could be changed to use i2c eeprom.
