allow to discard current write quest when catch exception

to avoid infinite recursion when writing an unrecognized object
add IProtocolEncoderOutput.MergeAll for merging wrote buffers
fix a bug when construct write requests in ProtocolCodecFilter
Replacing ConcurrentQueue in decoder output with a Semaphore

in ProtocolCodecFilter
complete IoServiceStatistics.ResetThroughput
use AddOrUpdate instead in ConnectionThrottleFilter

to avoid multiple access to the dictionary
Accept addresses like 0.0.0.0 or in the InSubnet()

and support IPv6 address
IncreaseWrittenMessages has been moved to TailFilter.MessageSent
bind test starts from 1024
Printed out the sent message (we were getting an empty byte before).
add default local endpoint in IoConnector
implement InputClosed() in test
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