STM32 Toolchain and Flash Loader

[Toolchain]

  * use "GNU ARM Embedded Toolchain]

  * https://launchpad.net/gcc-arm-embedded/+download

[Flash Loader]

  * Windows
    - use the "STM32 Flash Loader Demonstrator"
    - http://www.st.com/en/development-tools/flasher-stm32.html

  * Linux / Mac
    - Java      : STM32 USART Bootloader => https://sourceforge.net/projects/bootstm32/
    - Python : stm32loader script             => https://github.com/jsnyder/stm32loader
    - C          : stm32ld                              => https://github.com/jsnyder/stm32ld