Add functionality of automatically scrolling output log (scrolls down, as new data arrives, stops scrolling if you manually scroll up).
python2.5 compatibility
pep8 for contrib
Merge ingo-budde/buildbot:autoscroll-log-output (PR #1078)
Merge branch 'master' into nine

Conflicts:
	common/validate.sh
	master/buildbot/status/web/templates/logs.html