BigInteger.java (BigInteger(String, int)): New constructor.

BigInteger.java (BigInteger(String, int)): New constructor.

	* java/math/BigInteger.java(BigInteger(String, int)): New constructor.
	(BigInteger(String)): New constructor.
	(not): Rewritten using version from Kawa's BitOps class.
	(valueOf): New private methods from Kawa's BitOps class.
	(swappedOp): ditto.
	(bitOp): ditto.
	(setBitOp): ditto.
	(and): Implemented.
	(or): Implemented.
	(xor): Implemented.
	(andNot): Implemented.
	(clearBit): Implemented.
	(setBit): Implemented.
	(bitCount): Implemented.
	(toByteArray): Implemented.

From-SVN: r31926