[MacPorts] #54509: nginx: add http2 to default variants

[MacPorts]

#54509: nginx: add http2 to default variants
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  Reporter:  mohd-akram   |      Owner:
      Type:  enhancement  |     Status:  new
  Priority:  Normal       |  Milestone:
 Component:  ports        |    Version:  2.4.1
Resolution:               |   Keywords:
      Port:  nginx        |
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Comment (by neverpanic):

 Ideally, we'd offer a single configuration of nginx and loadable modules
 that can be separately compiled and enabled. Unfortunately nginx only
 recently added loadable module support and quite a few third-party modules
 haven't caught up, so my ideal vision of having a full-featured 'nginx'
 port and a bunch of 'nginx-$module' ports is not possible yet.

 Until that is the case, the variants are the de-facto method to choose the
 module support you want in your nginx build, and we might as well keep
 http2 around for those who want to test with a non-HTTP/2 server.

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Ticket URL: <https://trac.macports.org/ticket/54509#comment:2>
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