Useful buffer debug routines
Add logging config for API tests
Revised JSSE SSL
At ConduitMock, do not mark eof on terminateWrites
At EngineMock.wrap/unwrap: account for PERFORM_REQUESTED_ACTION whenever current handshake status isd NOT_HANDSHAKING
At SSLEngineMock.unwrap, do not return NEED_UNWRAP handshake status if needUnwrap is not true
Add log messages to SSLEngineMock
At ConnectedSslStreamChannelReadWriteTestCase and at JsseSSlStreamConnectionTestCase: remove checks for handshake status, as this is algorithm dependent
At ConnectedSslStreamChannelReadWriteTestCase and JsseSslStreamConnectionTestCase: remove FIXME, as moving shutdownReads/Writes to threads is impractical
Remove FIXME marks from ssl tests regarding bug in flush: the bug is fixed
Remove implementation dependent code from JsseXnioSslTestCase
At SslStreamConnectionValidationTestCase: do not require validation of non-api method params
Expect an EOFException at closeWithoutFlushing SSL tests
Adapt StartTLS tests to new SSL implementation
Enable EOF flag and disable READ_READY whenever an unwrap operation returns CLOSED status (thus preventing "XNIO000812: Connection closed unexpectedly" errors)
Prevent inifinite loop at JsseStreamConduit.performIO when the dst buffer for a read operation is too small.
At JsseStreamConduit, terminateWrites on sinkConduit once WRITE_FLAG_FINISHED is enabled
Enable JsseSslConnection WRITE_FLAG_SHUTDOWN2 when flush has been executed and WRITE_FLAG_SHUTDOWN is enabled
For all JsseSslConnection.read methods, flush remaining data at readBufferResources if eof has been read but not all unwrapped bytes have been copied to dst buffers.
Prevent unnecessary Buffer.copy operation when performing IO (read operation) at JsseStreamConduit.

- also, as a side effect, prevent unnecessary logging message (entering this if statement without need
  was causing the corresponding log message to be print so many times that it made difficult to read what
  operations were really being performed)