Temperature sensor on launchpad_129 + Stellarpad default Demo

Hi,
as requested in #362 I made the same modification for the launchpad_129 too.
I don't have that version so it *Need to be Tested*!

An example similar to the one the Stellaris came when I bought it is now in Example.
I havent put it in the shared examples because only works on Stellarpad, but it needs no additional hardware.