[Buildbot] #3201: Update example for using codebases with the force scheduler

[Buildbot trac]

#3201: Update example for using codebases with the force scheduler
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Reporter:  dustin       |       Owner:
    Type:  enhancement  |      Status:  new
Priority:  minor        |   Milestone:  0.9.+
 Version:  master       |  Resolution:
Keywords:  docs         |
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Comment (by sa2ajj):

 Related to #2945?

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Ticket URL: <http://trac.buildbot.net/ticket/3201#comment:1>
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