IBC: persist counterpart channel before OnChanOpenAck

[alpe]

Summary

Counterparty.ChannelID not available in OnChanOpenAck callback implementation.

Problem Definition

In a previous version the Counterparty.ChannelID was available for an OnChanOpenAck callback implementation (read via channelKeeper.GetChannel(). Now the the channelID is empty.
The data is available at this stage but persisted only some lines after the callback call.

Proposal

It would be helpful if the channel data could be stored first so that the callback implementation could access it.

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[colin-axner]

The fix: reorder handler to execute core handling first and then application callback (as state above).