Curate most popular plugins

[medikoo]

Use case description

Currently Framework is very actively developed, with a lot of changes (in many times breaking) being proposed.
At same time community heavily depends on a plugins which are not updated accordingly, and already there were few cases reported of them being broken

To effectively move forward we need to ensure that popular plugins are kept in shape and that they work with latest version of a Framework

Proposed solution

1. Having analytics data available in Mixpanel, prepare a list of popular plugins.
2. Ensure that all those plugins are put in shape and meet following constraints:
   1. Have configured serverless as peerDependency - If plugin required a breaking change to support Framework v2, then prepare two updates. First that configures "serverless": "1" as peer dependency (and that it's followed with a release in current major). Second that introduces breaking changes, configures "serlveress": "2" as peer dependency (and it's followed with a release with plugin major being bumped
   2. If plugin introduces any properties to configuration, it extends the configuration schema with it
   3. Plugin usage does not trigger any deprecation
   4. Configure an integration sanity test within a Framework, that confirms that major plugin functionality works with current version of a Framework (ideally if all the plugins are tested with minimal number of service deployments, so best if we put them all together into one service). We should also ensure that no deprecations are reported when testing them (Introduce "deprecationsNotificationMode" #9024 should help in that)

Note: If we have a difficulties in pushing new updates, as plugin seems not maintained, and we have no success in contacting the author, we should attempt to gain the rights to publish new releases in our scope

Having above secured, whenever we're about to release a new Framework major, let's also propose a PR that updates curated plugins for it (in simplest scenario, it'll be just about updating peerDependencies to e.g. "2 || 3", and publishing a new patch release)

[medikoo]

I've looked into data, and we have

6 plugins used by more than 10% users
18 plugins used by 5%-10% users
16 plugins used by 1%-5% users

I propose to handle at least first 7 plugins (those which go beyond 2k users in a week), and then (seeing how time-taking it is) decide weather to follow with some others

/cc @pgrzesik

[medikoo]

Closing, as all PR's to plugins were issued