Create HTTP2 document for hosted servers

[danyork]

Per #10, goal is to create:

ose-web-http2-hosted.md

with:

• info about HTTP/2
• info to send to a web hosting provider requesting HTTP/2
• a list of web hosting providers known to support HTTP/2 (this should be fairly easy as we should be able to query the hosting providers - or sites hosted on them - and see the response)

We can use the -apache.md version as the template to start.

[danyork]

A training participant from one of our Chapters noted that HTTP/2 didn't work for his Chapter's site because the hosting provider was using aversion of Apache older than 2.4.26, which is when Apache began supporting HTTP/2. His hosting provider promised to upgrade, but this may be something for us to keep in mind with the documentation. Some hosting providers may be using older versions of Apache and their first step may be to upgrade.

[danyork]

If anyone reading this knows of web hosting providers who DO or do NOT support HTTP/2 (or an existing list of such hosting providers), please feel free to add that information as a comment here on this issue.