STM32F730Z8 support

[wtuz]

STM32F730Z8 not supported,

and urls no longer available in list_new_stm32.py
-->
URLS = [
'http://www.st.com/content/st_com/en/products/microcontrollers/stm32-32-bit-arm-cortex-mcus.product-grid.html/SC2154.json',
'http://www.st.com/content/st_com/en/products/microcontrollers/stm32-32-bit-arm-cortex-mcus.product-grid.html/SC2155.json',
'http://www.st.com/content/st_com/en/products/microcontrollers/stm32-32-bit-arm-cortex-mcus.product-grid.html/SC2157.json',
]

so i think, this will not work.