chore(formatting): Adds prettier-solidity plugin and formats contracts

[omarish]

I was reading through the YieldSpace implementation (very nicely done, btw) and noticed a couple small formatting inconsistencies, so this PR adds and enables these formatting plugins:

• "prettier-plugin-solidity": "^1.0.0-alpha.60",
• "solhint-plugin-prettier": "^0.0.5"

This PR also adds another task to package.json: prettier:sol which will run all solidity code through prettier and write the formatted version. I would have named it lint:sol but that task name is already taken by solhint.

Finally, this PR touches a lot of solidity code and I haven't had a chance to look through very closely and make sure nothing was inadvertently changed by prettier (i.e if there's a bug in prettier that changes some solidity functionality by mistake). Ran the test suite and it's all passing.

[aniemerg]

@omarish is it possible to exclude files when running prettier? This appears to be a general improvement to style, but I think that it makes certain things worse, like the interface files. They go from being easy-to-skim function definitions to something far more unruly.

[omarish]

Yeah, absolutely. You can add a .prettierignore file with filename patterns you'd like to ignore.

[alcueca]

Too many conflicts, and the repo is being mostly archived.

[omarish]

Makes sense! I'm really impressed w/what you guys have built here. 💪