Code cleanup

[iAdramelk]

We are preparing to migrate from nextjs to gatsby, and to make migration easier, I made some code cleanup. Cleanup goals were to make folder structure more comfortable to use with gatsby, separate next-specific code from react components and remove as much next.js stuff that we didn't need as possible.

There is a lot of changes. To make it easier to review and read, I tried to group different tasks to different commits, so it will probably be easier to read it commit by commit then to read full diff.

What have been done:

• 7748c86 Move react components to components folder. Gatsby stored pages in the src/pages folder, but we are storing our components here too. To make it easier to navigate and distinguish between them, I moved components to the subfolder src/components.
• fa371db and 7bf941f Consistently rename components and styles files. Most of our components are named Component/index.js, but some older components are named Component/Component.js, I renamed all such components to the newer format.
• 9258f52, 57b33bf, 81cdee8, 50beb01 - I split pages to the two separate components - one responsible for render and visual styles (moved to src/components) and one responsible for routing, header data and getting initial props from API (left in the pages folder). Because I will need to refactor pages logic from nextjs to gatsby, it will be easier to do if there is no presentational logic in them.
• 59e399d Move styled-components to separate files. After we migrate to gatsby, we wouldn't need styled-components anymore. To make replacing them easier in the future, I moved them all to separate files with the same logic as was used on the community page.
• 74c6597 Refactor NextLink and NextRouter. Here I create a standard link component and use it instead of the next/link in our files; this way, we will only need to replace for gatsby-link in one place. Also, here I removed some cases of next/router usage that we don't need.

[jorgeorpinel]

Thanks @iAdramelk. Massive but greatly explained PR!

Move styled-components to separate files

Nice. Should we also rename all the styles.js files to styled.js (per a conversation had some time ago). (Never mind, see next point.)
Also, do you think the issues below are still valid now?

• glossary: soft code style constants in tooltip file glossary: soft code style constants in tooltip file #658
• js: refactor repetitive React components js: refactor repetitive React components #777

After we migrate to gatsby, we wouldn't need styled-components anymore

Let's try remembering to close css: migrate from styled comps to plan css or css-modules #792 when that happens.

Thanks!

[iAdramelk]

@jorgeorpinel Thanks! I think that #658 and #777 are still valid, but I'd place them on hold for now, before we finish with Gatsby and decide where to migrate styles.