Add deactivate-intent to plugin deactivation

[moorscode]

When disabling the plugin we want to provide the user with a modal in which the intent of the deactivation can be supplied.

The plugin Monster Insights is providing this functionality already and is the inspiration for this feature:

The options provided to the user should be checked with the Product-team before merging.

The code that is being used in the Monster Insights plugin should be taken as a base.
The information should be sent anonymously to Yoast.com to add it to our logging system.

[schlessera]

Watch for GDPR pitfalls. Sending this feedback anonymously still transmits a lot of information that might or might not be problematic:

• a given user with IP (A)
• was using plugin (B)
• while using the browser (C)
• on the platform (D)
• and stopped using the plugin because (E)

[Volnus]

Just going to pop in, I find these popups to be utterly annoying and frustrating when disabling plugins.

[jonoalderson]

More thoughts. I'm reasonably confident that few people understand that deactivating the plugin "un-SEO's" their site; we should throw some warnings/notifications to make this clear - perhaps with greater priority than seeking feedback.

I'll aim to scope more specifically later this week.