Fix ESLint Ignores and Extract Fn

[Timer]

This extracts __overrideCssConfiguration to clean up the CSS file prior to Sass support.

Also, I fixed some outstanding TODOs by upgrading ESLint and removing ignore rules. 🚀

[ijjk]

Stats from current PR

Default Server Mode (Decrease detected ✓)

General Overall decrease ✓

	zeit/next.js canary	Timer/next.js refactor/__overrideCssConfiguration	Change
buildDuration	14.9s	14.9s	⚠️ +36ms
nodeModulesSize	48.9 MB	48.9 MB	-409 B

Client Bundles (main, webpack, commons)

	zeit/next.js canary	Timer/next.js refactor/__overrideCssConfiguration	Change
main-HASH.js gzip	5.12 kB	5.12 kB	✓
webpack-HASH.js gzip	746 B	746 B	✓
4952ddcd88e7..54d3.js gzip	4.68 kB	4.68 kB	✓
commons.HASH.js gzip	4.06 kB	4.06 kB	✓
de003c3a9d30..d6b9.js gzip	16.3 kB	16.3 kB	✓
framework.HASH.js gzip	39.1 kB	39.1 kB	✓
Overall change	70 kB	70 kB	✓

Client Bundles (main, webpack, commons) Modern

	zeit/next.js canary	Timer/next.js refactor/__overrideCssConfiguration	Change
main-HASH.module.js gzip	4.15 kB	4.15 kB	✓
webpack-HASH..dule.js gzip	746 B	746 B	✓
4952ddcd88e7..dule.js gzip	5.56 kB	5.56 kB	✓
de003c3a9d30..dule.js gzip	15.1 kB	15.1 kB	✓
framework.HA..dule.js gzip	39.1 kB	39.1 kB	✓
Overall change	64.7 kB	64.7 kB	✓

Legacy Client Bundles (polyfills)

	zeit/next.js canary	Timer/next.js refactor/__overrideCssConfiguration	Change
polyfills-HASH.js gzip	4.76 kB	4.76 kB	✓
Overall change	4.76 kB	4.76 kB	✓

Client Pages

	zeit/next.js canary	Timer/next.js refactor/__overrideCssConfiguration	Change
_app.js gzip	1.34 kB	1.34 kB	✓
_error.js gzip	4.07 kB	4.07 kB	✓
hooks.js gzip	779 B	779 B	✓
index.js gzip	222 B	222 B	✓
link.js gzip	2.89 kB	2.89 kB	✓
routerDirect.js gzip	283 B	283 B	✓
withRouter.js gzip	282 B	282 B	✓
Overall change	9.87 kB	9.87 kB	✓

Client Pages Modern

	zeit/next.js canary	Timer/next.js refactor/__overrideCssConfiguration	Change
_app.module.js gzip	769 B	769 B	✓
_error.module.js gzip	3.06 kB	3.06 kB	✓
hooks.module.js gzip	371 B	371 B	✓
index.module.js gzip	212 B	212 B	✓
link.module.js gzip	2.46 kB	2.46 kB	✓
routerDirect..dule.js gzip	273 B	273 B	✓
withRouter.m..dule.js gzip	272 B	272 B	✓
Overall change	7.42 kB	7.42 kB	✓

Client Build Manifests

	zeit/next.js canary	Timer/next.js refactor/__overrideCssConfiguration	Change
_buildManifest.js gzip	61 B	61 B	✓
_buildManife..dule.js gzip	61 B	61 B	✓
Overall change	122 B	122 B	✓

Rendered Page Sizes

	zeit/next.js canary	Timer/next.js refactor/__overrideCssConfiguration	Change
index.html gzip	1.02 kB	1.02 kB	✓
link.html gzip	1.03 kB	1.03 kB	✓
withRouter.html gzip	1.02 kB	1.02 kB	✓
Overall change	3.07 kB	3.07 kB	✓

---

Serverless Mode (Decrease detected ✓)

General Overall decrease ✓

	zeit/next.js canary	Timer/next.js refactor/__overrideCssConfiguration	Change
buildDuration	15.3s	15.2s	-193ms
nodeModulesSize	48.9 MB	48.9 MB	-409 B

Client Bundles (main, webpack, commons)

	zeit/next.js canary	Timer/next.js refactor/__overrideCssConfiguration	Change
main-HASH.js gzip	5.12 kB	5.12 kB	✓
webpack-HASH.js gzip	746 B	746 B	✓
4952ddcd88e7..54d3.js gzip	4.68 kB	4.68 kB	✓
commons.HASH.js gzip	4.06 kB	4.06 kB	✓
de003c3a9d30..d6b9.js gzip	16.3 kB	16.3 kB	✓
framework.HASH.js gzip	39.1 kB	39.1 kB	✓
Overall change	70 kB	70 kB	✓

Client Bundles (main, webpack, commons) Modern

	zeit/next.js canary	Timer/next.js refactor/__overrideCssConfiguration	Change
main-HASH.module.js gzip	4.15 kB	4.15 kB	✓
webpack-HASH..dule.js gzip	746 B	746 B	✓
4952ddcd88e7..dule.js gzip	5.56 kB	5.56 kB	✓
de003c3a9d30..dule.js gzip	15.1 kB	15.1 kB	✓
framework.HA..dule.js gzip	39.1 kB	39.1 kB	✓
Overall change	64.7 kB	64.7 kB	✓

Legacy Client Bundles (polyfills)

	zeit/next.js canary	Timer/next.js refactor/__overrideCssConfiguration	Change
polyfills-HASH.js gzip	4.76 kB	4.76 kB	✓
Overall change	4.76 kB	4.76 kB	✓

Client Pages

	zeit/next.js canary	Timer/next.js refactor/__overrideCssConfiguration	Change
_app.js gzip	1.34 kB	1.34 kB	✓
_error.js gzip	4.07 kB	4.07 kB	✓
hooks.js gzip	779 B	779 B	✓
index.js gzip	222 B	222 B	✓
link.js gzip	2.89 kB	2.89 kB	✓
routerDirect.js gzip	283 B	283 B	✓
withRouter.js gzip	282 B	282 B	✓
Overall change	9.87 kB	9.87 kB	✓

Client Pages Modern

	zeit/next.js canary	Timer/next.js refactor/__overrideCssConfiguration	Change
_app.module.js gzip	769 B	769 B	✓
_error.module.js gzip	3.06 kB	3.06 kB	✓
hooks.module.js gzip	371 B	371 B	✓
index.module.js gzip	212 B	212 B	✓
link.module.js gzip	2.46 kB	2.46 kB	✓
routerDirect..dule.js gzip	273 B	273 B	✓
withRouter.m..dule.js gzip	272 B	272 B	✓
Overall change	7.42 kB	7.42 kB	✓

Client Build Manifests

	zeit/next.js canary	Timer/next.js refactor/__overrideCssConfiguration	Change
_buildManifest.js gzip	61 B	61 B	✓
_buildManife..dule.js gzip	61 B	61 B	✓
Overall change	122 B	122 B	✓

Serverless bundles

	zeit/next.js canary	Timer/next.js refactor/__overrideCssConfiguration	Change
_error.js gzip	60.5 kB	60.5 kB	✓
hooks.html gzip	1.06 kB	1.06 kB	✓
index.js gzip	60.9 kB	60.9 kB	✓
link.js gzip	77.8 kB	77.8 kB	✓
routerDirect.js gzip	75.9 kB	75.9 kB	✓
withRouter.js gzip	75.9 kB	75.9 kB	✓
Overall change	352 kB	352 kB	✓

Commit: ceb8c0c