ACCUMULO-1959 Deprecate Value(ByteBuffer,boolean)

The Value constructor that takes a ByteBuffer and a copy flag does
an unnecessary double copy when the flag is true. This change
deprecates the constructor in favor of the one without the flag
(which always performs a copy).

Signed-off-by: Josh Elser <elserj@apache.org>
ACCUMULO-1959 - supressing deprecation warning