Vhal fixes and DS1307

Hello,

just released the following upates:

  • board.zerynth.st_nucleof401re r1.0.6  and vm.zerynth.st_nucleof401re r1.0.6: fixed I2C2 issues (bad pin configuration)
  • core.zerynth.stdlib r1.0.3: some threading fixes, mcu module now gives access to the mcu uid and adc module allows to change the adc sampling frequency.
  • vhal.zerynth.armcmx_atmelsam3x r1.0.2: I2C fixed!
  • vhal.zerynth.armcmx_stm32f_common r1.0.2: removed I2C debug messagges :expressionless:
and also a new library for the DS1307 realtime clock! lib.maxim.ds1307