Deprecated timeout().never(), in line with timeout().atMost()

Timeout().atMost() is deprecated due to issue 235: https://code.google.com/p/mockito/issues/detail?id=235

These exact same arguments apply to never(); both verification modes are extremely likely to create assertions that immediately pass, and do not test what they're intended to test. This patch therefore deprecates never() similarly.

Fairly shortly I'm also planning on implementing verify(mock, during(x).[...]), as a counterpart to timeout which always waits the full time, as discussed in issue 347: https://code.google.com/p/mockito/issues/detail?id=347. This should allow for the kind of assertion behaviour that timeout().never() implies.

(Also some minor whitespace tidy up and spelling corrections)