[MacPorts] #52984: Upgrade camlp5 to 6.17

[MacPorts]

#52984: Upgrade camlp5 to 6.17
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  Reporter:  pmetzger  |      Owner:
      Type:  update    |     Status:  new
  Priority:  Normal    |  Milestone:
 Component:  ports     |    Version:  2.3.5
Resolution:            |   Keywords:  haspatch
      Port:  camlp5    |
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Comment (by mf2k):

 [http://thegreyblog.blogspot.com/2014/08/writing-macports-portfile-and-
 testing.html This website] seems to have a good description of using the
 github portgroup.

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Ticket URL: <https://trac.macports.org/ticket/52984#comment:4>
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