@Test
  public void numberOfBitsInNegativeIntegerKernighanMethod() {
    assertEquals(30, bitsCounter.countNumberOfBitsLogN(-7));
  }
A negative number is represented by calculating its complement and adding 1 to
the result (Two's complement).
eg. ~7 + 1
src/test/java/com/github/pedrovgs/problem1/BitsCounterTest.java