Revert "ipfilter implementation for netty 4/5 [#2129]"

Motivation:
ipfilter implementation may need a bit more time to stabilize.

Modifications:
Revert the commit that added it to 4.0 branch (it is still included in 4.1 and master)

Result:
ipfilter will not be included in the next 4.0.x release (just as before9