[Buildbot] #2945: Add an example of using codebases

[Buildbot trac]

#2945: Add an example of using codebases
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Reporter:  sa2ajj            |       Owner:  Ben
    Type:  enhancement       |      Status:  assigned
Priority:  patches-accepted  |   Milestone:  0.9.+
 Version:  master            |  Resolution:
Keywords:  docs              |
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Comment (by sa2ajj):

 Based on the
 [http://irclogs.jackgrigg.com/irc.freenode.net/buildbot/2014-11-07#i_3490587
 IRC discussion], a couple of different codebase mappings need to be shown
 and how they are handled by different schedulers should be explained.

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Ticket URL: <http://trac.buildbot.net/ticket/2945#comment:3>
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