Move ICS4Wrappers from keepers to IBCModule implementations

[colin-axner]

Summary

Currently, many of the keepers for IBC modules hold the ICS4Wrapper (upward calling in IBC stack). The ICS4Wrapper reference should be held by the IBCModule implementation itself

Problem Definition

An SDK chain declares only 1 keeper per application, but defines many IBC modules (potentially 1 per stack). It should be possible for different instances of the same IBC module to reference different ics4wrappers

Proposal

Move ics4wrappers to IBCModule implementations. Otherwise it would not be possible to do the following:

// transfer -> fee -> channel
// ica controller -> fee -> extra module -> channel

As the ics4wrapper is on the fee keeper which is shared between the 2 stacks despite having separate instances of fee.IBCModule

---

For Admin Use

• Not duplicate issue
• Appropriate labels applied
• Appropriate contributors tagged/assigned