rename Date assertions isWithinXXX to hasSameXXXAs

[joel-costigliola]

I was never comfortable with isWithinXXX assertions (event though it was my idea ...), reading them after a while, I find it confusing, if you write ...

assertThat(date).isWithinSecond(otherDate);

... then do you want to compare seconds field of dates only or dates to seconds precision (in our case it is second field comparison only).

I come up with a clearer name (I think) : hasSameXXXFieldAs

So instead of

assertThat(date).isWithinSecond(otherDate);

We would have

assertThat(date).hasSameSecondFieldAs(otherDate);