Add copyTo(ByteBuffer) to AnyObjectId

Change-Id: I3572f6113db883002f9c3a5ecc1bcc8370105c98
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

org.eclipse.jgit/src/org/eclipse/jgit/lib/AnyObjectId.java

@@ -339,6 +339,16 @@ public abstract class AnyObjectId implements Comparable {
 		formatHexByte(b, o + 32, w5);
 	}
 
+	/**
+	 * Copy this ObjectId to a ByteBuffer in hex format.
+	 *
+	 * @param b
+	 *            the buffer to copy to.
+	 */
+	public void copyTo(ByteBuffer b) {
+		b.put(toHexByteArray());
+	}
+
 	private byte[] toHexByteArray() {
 		final byte[] dst = new byte[Constants.OBJECT_ID_STRING_LENGTH];
 		formatHexByte(dst, 0, w1);