Adding the maxVA and minVA methods to NumberUtils and test methods


Adding the following methods to NumberUtils:
* `public static long maxVA(final long... number)`
* `public static long maxVA(final int... number)`
* `public static long maxVA(final short... number)`
* `public static long maxVA(final byte... number)`
* `public static long maxVA(final double... number)`
* `public static long maxVA(final float... number)`
* `public static long minVA(final long... number)`
* `public static long minVA(final int... number)`
* `public static long minVA(final short... number)`
* `public static long minVA(final byte... number)`
* `public static long minVA(final double... number)`
* `public static long minVA(final float... number)`