[Buildbot] #3437: format configuration file syntax errors in more friendly way

[Buildbot trac]

#3437: format configuration file syntax errors in more friendly way
----------------------+------------------------
Reporter:  rutsky     |       Owner:
    Type:  undecided  |      Status:  new
Priority:  major      |   Milestone:  undecided
 Version:  0.9.0b6    |  Resolution:
Keywords:             |
----------------------+------------------------

Comment (by dustin):

 Just the requested changes

--
Ticket URL: <http://trac.buildbot.net/ticket/3437#comment:5>
Buildbot <http://buildbot.net/>
Buildbot: build/test automation