[Buildbot] #3106: log www plugins on startup

[Buildbot trac]

#3106: log www plugins on startup
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Reporter:  dustin       |      Owner:  dustin
    Type:  enhancement  |     Status:  new
Priority:  minor        |  Milestone:  0.9.0
 Version:  master       |   Keywords:
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 This will help debug what is and is not installed..

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Ticket URL: <http://trac.buildbot.net/ticket/3106>
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Buildbot: build/test automation