Add STM32F3DISCOVERY example

[mlout]

• Update CANopenNode to the latest available version. I have checked that all existing example projects still compile. I do not have the hardware to test them all unfortunately.
• Add example project for STM32F3DISCOVERY which uses CAN and FreeRTOS
• Add a different locking implementation which can be used with FreeRTOS. This can be enabled using the USE_FREERTOS_LOCKING preprocessor symbol. This is enabled in the example project mentioned above.
• Add a flash storage example for writing Object Dictionary values to the flash memory. This is only tested on STM32F3xx MCUs! This can be enabled using the USE_CO_STORAGE_FLASH preprocessor symbol. This is enabled in the example project mentioned above.
• Fix some printf format specifier warnings in CO_app_STM32.c