[FW-94] Changes in ADC + included tests

[jdmarmen]

• Changes in ADC:

1. The original implementation wasn't accessing the pins memory location, it was creating a copy. Changed the implementation to work with pointers.
2. Added the pin type selection inside inscribe(), as it wasn't done.
3. Added a map to pair each ADC pin ID with it's corresponding pin.
4. More changes on inscribe() start() and get_value_pointer() to support the new implementation.
5. Small changes on SharedMemory::get_pin().

• Added ADC tests