feat: update dependencies / general cleanup

[dcodeIO]

While looking into the jsdoc issues, especially #1338, I figured that we should instead update all the dependencies. So this PR

• Updates all the dependencies to their most recent versions (this was surprisingly painless so far)
• By that, fixes any audit issues
• Fixes any linting issues
• Fixes a problem with the main package importing long, which was breaking generated typings
• Fixes an issue with BufferWriter.alloc not being correctly recognized as a function (aynmore?) during type generation
• Updates distribution files
• Reorganizes scripts and runs more of them during CI
• Adds a workaround for broken top-level enums in jsdoc

On a glimpse everything seems to be working just fine after doing so, but the sheer amount of problems this can theoretically trigger still makes me nervous. So, if anyone here has the nerves to try it and validate that the jsdoc issue is gone, that the dist files still work, or that the CLI doesn't do anything unexpected now, please do :)

[dcodeIO]

Regarding the JSDoc problem, from what I can tell now it seems that something broke in JSDoc a while ago related to top-level enums, which is still not fixed entirely, but also doesn't seem as bad as it once was (?). Not sure. There is a workaround in place now for top-level enums specifically (@exports + @enum not having a global scope, but none) that I hope will catch exactly this bug, and become a nop with a potential fix even if we forget it exists.

Also, there's a lot more that could be done in addition to the changes proposed here, like replacing deprecated tslint, continuing to make the CLI its own package and introducing a friendlier code style, but well.

[Flarna]

I tried your changes in my project and it looks fine. Did not test that much but at least generation of typescript definitions with node.js 12 works now.

[dcodeIO]

Got this up to date again, but besides checking OK, it appears there's something strange happening with CI now that I've never seen before?

[alexander-fenster]

@dcodeIO This is indeed weird. I was able to fix the CI thing by disabling all branch protection for master and then re-enabling it back for the lowercased tasks, which immediately brought the checks for this PR back to normal. I'm guessing, some wires got crossed incorrectly in GitHub Actions?

Anyway, right now the checks look good (all required, and all green), we can move forward!