Pioneer / joystream-js outstanding work

[Lezek123]

List of tasks to prioritize:

1. Reconstructing joy-utils in a way that it can become a part of a joystream-js library, resuable beyond Pioneer.

• Start by extracting out some reusable parts of joy-proposals (transport, components, hooks etc.) - DONE
• Continue with other packages like joy-media, joy-members etc. (POPSTPONED)

2. Fix Pioneer linter issues.
Related PR: #509

• Perform auto-fix first (reduces ~80% of the errors) - DONE
• Get rid of the linter rules that doesn't make that much sense in this project (like react-proptypes) - DONE
• "Manually" fix the remaining errors - DONE

3. joystream-api-examples (UPDATE: Issues fixed in Joystream/joystream-api-examples#3)

There are a few issues there:

• Types are outdated - FIXED
• Doesn't compile when using a newer version of TS (see: TypeError: Cannot read property 'flags' of undefined joystream-api-examples#2. This is quite a common problem, I think I already encountered it with status-server, pioneer etc.) - FIXED (by modyfying ts version in package.json)
• When those 2 issues are resolved we get an error:

TypeError: Class extends value undefined is not a constructor or null
    at Object.<anonymous> (/home/leszek/projects/joystream/joystream-api-examples/node_modules/@joystream/types/lib/content-working-group/index.js:11:35)

Which looks like a circular reference error caused by the import chain: roles => members => index => content-working-group => members (I cannot reproduce this error with @joystream/types in the monorepo, even though they should be consumed the same way ie. on this branch: #469). Further investigation needed... - FIXED (in joystream-api-examples, but a fix in @joystream/types will probably be required to prevent those kinds of errors in the future)

4. Finish the process of migrating Pioneer into the monorepo

• Clean and move Pioneer (https://github.com/Joystream/apps) issues into this monorepo (https://github.com/Joystream/joystream)
• Add note in Pioneer's repo README.md about the migration