The Hamming distance between two numbers is defined as the
number of positions in their binary representations at which they
differ (leading zeros are used if necessary to make the binary
representations have the same length)  e.g., the numbers "11010"
and "01100" differ at the first, third and fourth positions, so
they have a Hamming distance of 3.
You will be given a String[] numbers containing
the binary representations of some numbers (all having the same
length). You are to return the minimum among the Hamming distances
of all pairs of the given numbers.
