improve documentation and README

[jkeesh]

Hi--

Really cool slackbot integration you guys have built, so thank you!

I was able to get it set up but there was a bunch of stuff that I think could have been clearer in the docs

• The documentation was split up across the forum, the README, and the video. I think it would be helpful if the README contained more of the information. Even just the basics of how to create a command, it was not clear to me without a bunch of digging that a custom command was a look on a dashboard within a specific space set by an environment variable that I had already launched...
• For a heroku deployment, docs seem out of order. If you actually follow the order of the instructions on the docs, you'll get errors, just because of when URLs are generated etc
• The readme documentation for creating a bot user is incorrect if your slack organization does not have any existing bot users. The menu path you write on the readme actually didn't exist for me. I had to go create a bot through a different pathway.
• To make the docs and setup a bit more foolproof, you may want to include a bit more info on s3 bucket setup. It's not too complicated but by centralizing this all in the documentation you make it easier to set up. The reason it could be worthwhile is there are still several steps, setting up the s3 bucket, provisioning the new user, writing their policy for permissions... easy to mess up at several steps along the way. You could just write a section on the s3 bucket in a couple of paragraphs and people could skip if they know how
• Include a link to the marketing video on the readme
• Change outline of README headers-- the info for setting up your own server is sprinkled around other different comments around data access, slash commands etc.
• Still unsure right now about how you set up filters through commands to the bot (I'll figure it out soon, but this could be explained in the docs and save some time!)

Thank you for the cool tool!