Scanner update 3 (with other stuff)

[ONGOING] first_scan method of scanner is almost finished. Only ints are
supported, just need to add other types and fix a bug when too much
values are scanned.
[CODE] Added __len__ method to scanner object
[CODE] Added  __getitem__ method. It returns a tuple of (value scanned,
addr)
[BUG] On dealloc, a scanner object free its buffer
Scanner update 3 header

Updated header with scanner update 3