WIP: Release 5.0

[Ipstenu]

Jumping over 4.9 (I know) to bring in major changes:

• Remove remote dependancy for scans -- they don't change enough for that to be needed anymore
• Scan now saves last-run data per domain
• Support Health Check (uses saved scan results)
• Multiple IPs (fixes #62 )
• Remove redundant age check (fixes #87)
• Add purge for when someone's using customizer (fixes #85)
• Add purge support for pending and draft statuses (fixes #39)
• Add fix for Cloudflare and sslverify
• Add in DreamPress only schema defaults, which is not my fav thing but...

[Ipstenu]

Sorry about the length delay in forward progress. It was held up due to internal work that is directly related to testing on Varnish v 6 :) And yeah, it works 👯‍♀️