[Buildbot] #3403: replace pep8+pyflakes with flake8

[Buildbot trac]

#3403: replace pep8+pyflakes with flake8
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Reporter:  rutsky     |       Owner:  rutsky
    Type:  undecided  |      Status:  assigned
Priority:  major      |   Milestone:  undecided
 Version:  master     |  Resolution:
Keywords:             |
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Comment (by rutsky):

 First part of the work to resolve this issue:
 https://github.com/buildbot/buildbot/pull/1951

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Ticket URL: <http://trac.buildbot.net/ticket/3403#comment:3>
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