Implement IBC ratelimit

[shaolin-flow]

Overview

Kind folks at Stride open sourced the IBC rate limit module here. As noted by the Stride team:

The module is meant as a safety control in the event of a bug, attack, or economic failure of an external zone. It prevents massive inflows or outflows of IBC tokens to/from Stride in a short time frame.

Implementing this module will be a beneficial security measure taken for IBC-enabled RollApps. As the utilization of the Dymint client is new in the ecosystem we must take all necessary precautions with regards to bridging assets across blockchains.

Proposal

Review and implement the ratelimit module by the Stride team for rate limiting IBC channels.