Add reaction modification, correct thread updating

[shahyar]

• Add ability to toggle message emoji reactions Does not include the reaction menu. This only adds the ability to +1 or -1 an existing reaction.
• Dispatch MessageList events to thread children This fixes how thread messages do not correctly receive updates, nor do they update the thread's parent message in the channel. There's definitely a better way of doing this, but this is a good stop-gap measure.
• Store messages by ID in messageList This is a less drastic version of my last patch to change the data structure. It's not necessary, but the commits for dispatching MessageList events will be way more optimized if we can reference messages directly by ID. This is similar to how
• Optimize readMessagesImpl to work in 1 pass
• Fix replace when id is a Number
• Clean up user storage logic to account
• Add back chat room header Could live without this, but it's nice to have the channel header in. Still not sure why channel purpose don't show up correctly; they're all listed as "(No description)".
• Fix error when going up DOM tree at parent.tagName
• Fix sorting channels by isMuted
• Set minimum version to node 8.11.2 Potential fix as described by websockets/ws#1354 and slackapi/node-slack-sdk#531

[zcbenz]

Thank you for working on this. But to be honest, the time I can spare on this project is rather limited, and reviewing refactoring code is very stressing to me, it is likely that you are writing code much faster than I can review them.

For this project I enjoy writing code more than reviewing them, and I think it is unfair to reject your changes with my own personal taste. So I would suggest forking the project with another name, and I would be happy to add the link to this repo's README.

Sorry if I have wasted your time preparing the code for review, I'll review this PR and get some of the changes into master when I have time.

[tuananh]

maybe split them up to smaller PR to make it easier for reviewing?

[shahyar]

I'm in no rush to get these changes landed. I also don't usually have a lot of time to work on code, but I was motivated by my organization's terrible Slack performance. So, I'm unlikely to maintain a fork. Plus having Yue be able to render layered subviews is critical to the future of this project. Once you have that, I'm sure you'll have more contributors who can maintain this app with you and/or for you.

I would assume the stressful commit is 87f4032d5a837de837ceb018f724661481014f09, so we can omit that one and everything else should still work just fine.

[zcbenz]

Thanks for your understanding, I have cherry picked commits that do not have changes to code structures. Basically I would like to keep the data structures as simple as possible, so it won't increase complexity when adding support for more services in future.

Also for the channels header, it is not yet ready because of https://github.com/yue/wey/pull/47#issuecomment-383080020.