• added ability to cache VAPID headers in a request (thx @javiermarinros!)
• enhanced message reporting (thx @t1gor!)
• made flush really async (thx @marcvdm!)
• fixed an encryption error that would occur when using the new subscription structure with a contentEncoding (thx @soerenuhrbach!)
• fixed an error that would occur if network request failed (thx @steffenweber!)
• fixed some static errors