Update entry page to better explain the benefits of podman

Hi!

I've received the following comment on Twitter:

https://twitter.com/bobschi/status/1262740627160064000?s=20

While for the tech. ppl. the explanation on podman.io is eventually fine, for non-tech. ppl., this might not be that obvious. Could the start page be reworked so it clearly points out the benefits in contrast to ?

Thanks,
Oliver

Start by reviewing the podman.io entry page and the linked Twitter comment to understand the concern about explaining Podman's benefits to non-technical readers. Done means the start page has clearer benefit-focused wording and a more understandable comparison with the intended alternative, with the result checked in the rendered page.

Written by the indexing model from the issue text.