The active record connection adapter should use migrations instead of auto config

The Connection table AutoConfig keeps causing people problems.

This should be done via a migration that is added by the installer.

In the meantime you can easily turn off the autoconfig by adding this line to the end of your hyperstack.rb initializier:

`def (Hyperstack::Connection).build_tables?; false; end`

This will stop AutoConfig from building the tables, and the whole connection and broadcast mechanism will just not work (but will cause no problems) until the tables exist from the migration.

The migration would look like this:

```ruby
class AddHyperstackTables < ActiveRecord::Migration[5.2]
def change
create_table "hyperstack_connections", force: :cascade do |t|
t.string "channel"
t.string "session"
t.datetime "created_at"
t.datetime "expires_at"
t.datetime "refresh_at"
end

create_table "hyperstack_queued_messages", force: :cascade do |t|
t.text "data"
t.integer "connection_id"
end
end
end
```

Here is some info on creating the migration from the generator:

https://api.rubyonrails.org/classes/Rails/Generators/Migration.html