JNI's getBytesSockopt and setBytesSockopt should take care of null termination

[Kentzo]

C-API returns and accepts null-terminated strings. Java doesn't care about them.

Current implementation requires extra work from the user to remove and add null termination. I think JNI should be modified to handle this implicitly, however this change will break all code that has "hacks" to remove / add null-terminator.