[Buildbot] #3483: rewrite usage of virtualenv in firstrun docs

[Buildbot trac]

#3483: rewrite usage of virtualenv in firstrun docs
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Reporter:  rutsky     |       Owner:
    Type:  undecided  |      Status:  new
Priority:  major      |   Milestone:  0.9.+
 Version:  0.9.0b7    |  Resolution:
Keywords:  simple     |
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Changes (by rutsky):

 * milestone:  0.9.0 => 0.9.+


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Ticket URL: <http://trac.buildbot.net/ticket/3483#comment:2>
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