It fails due to -O2 warning.

Don't leak higher bits in putWord8 and putWord16be

 - copy-paste make_mask from Get.hs
 - use it

Bug discovered by Alexander Polakov.
We change how putBool works to expose it, making it easier to fix,
lots of tests in the test suite breaks by this change,
but they shouldn't.
putWord8 is broken, as it may let bits we want to be unused leak into
the output. If some high bits are set in a Word8, but we don't want to
output them, they will anyway leak and corrupt previously written bits.
The following program is now broken with this commit;

broken = do
 putBool False
 putBool True

It'll output a byte: 11000000
instead of the expected: 01000000

getLazyByteString: read current byte + isEmpty

 suggested by @kolmodin

 - remove stupid Bool comparisons
 - no need for numeric parameter in prop_isEmptyOfConsumedEmpty

 suggested by @kolmodin

Don't allow block merging for this function, as
blocks are always done on strict bytestrings.

Issue reported by Eugene Kirpichov <ekirpichov@gmail.com>.

Using the ensureN, get and put methods from binary-0.6.0.0 we
can keep the current chunk within the BitGet monad and put what
remains of the chunk when the monad has finished executing or
if we encounter an error.

Return the empty string if n<=0.

We should do this conditionally, only not needed if random>=1.0.1.0.

If not checking the requested read length, we're most likely to
segfault.