Added file for ADC module.
First implementation of ADC module.
Adding forgot statement of a function.
Adding other forgot statement of a function.
Merge branch 'feature/adc'
Fix a functions name on SPI module.
Added some utility function to convert number to string and viceversa.
Added implementation of xtu8 function.
Added implementation of xtu16 function.
TODO: Three function for the same thing. Fix it!
Merge branch 'feature/rtc'
Added implementation of u32tx function.
TODO: Three function for the same thing. Fix it!
Added RTC alarm functions.
Added interrupt list for KL series.