Coin counter resets on overflow

[andersondomingues]

V4:

When adding a coin with the coin counter at max (=0x1F), the coin counter resets, as shown in the attached picture.

Possible solution: returning the newly inserted coin

1. switch no a special state
   ...
elsif m100 = '1' then
if count < MAX_COUNT then pe <= soma;
   else pe <= devolve2;
   end if; else ...`

2. update D100 to reflect the special case
   d100 <= '1' when (ea = devolve or ea = devolve2) else '0';

3. add the new state to the state enumeration
   type state is (action, soma, sgreen, satum, sbacon, nulo, devolve, devolve2);

4. create a new constant (for the sake of readability)
   constant MAX_COUNT : integer := 2**(count'length)-1;

    		else