a5006c1969
Motivation: EventLoopGroup.register doesn't need the Channel paramter when ChannelPromise is provided as we can get the Channel from ChannelPromise. Resolves #2422. Modifications: - Add EventLoopGroup.register(ChannelPromise) - Deprecate EventLoopGroup.register(Channel, ChannelPromise) Result: EventLoopGroup.register is more convenient as people only need to set one parameter.