Typed stores

[hu55a1n1]

With the current store implementation, users can write arbitrary data to any path. This can be problematic because we know that some paths are only meant to store a certain type of data. For example -> paths of the form "clients/{identifier}/clientState" will always store ClientState. Here are some properties that would be nice to have ->

• Enforce this at the type level
• Disallow creation of multiple stores that point to the same path
• Provide a way for users to define the (de)serialization at the type level.

[hu55a1n1]

A decent implementation of this concept for the IBC module will require informalsystems/hermes#1760 to be merged.