Moved relayer/cli to relayer-cli, relayer/relay to relayer

[greg-szabo]

Closes: #180

Description

Steps made in the change:

• Moved the relayer/cli folder to relayer-cli
• Moved the relayer/relay folder to relayer
• Updated Cargo.toml to point to relayer-cli and relayer respectively
• Updated relayer-cli/Cargo.toml to point the relayer dependency to ../relayer instead of ../relay

I wanted to minimize any changes because moving such a big amount of files is hard to review.

• After a bit of contemplating, I've updated the CHANGELOG file too. We should get in the habit of it even when a lot of files are involved.

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For contributor use:

• Unit tests written
• Added test to CI if applicable
• Updated CHANGELOG_PENDING.md
• Linked to Github issue with discussion and accepted design OR link to spec that describes this work.
• Updated relevant documentation (docs/) and code comments
• Re-reviewed Files changed in the Github PR explorer

[greg-szabo]

Give me a few minutes to fix all the other paths I didn't think about.

[andynog]

The changes looks good to me. Just one question, should we call the modules folder 'ibc-module' or something like this ?

Also, should we take this repo refactoring opportunity to start adding information to this issue ?

[greg-szabo]

I wouldn't put the ibc- prefix in front of any of the folders. It's the IBC repository, so we should assume that everything is ibc-related.

The crate.io crates should have the ibc- prefix, but we can discuss that in its own issue. (#142 and cosmos/ibc-rs#125)