Add support for sequences of fully automated tests.
Add support for sequences of fully automated tests.

Paired with CL: http://codereview.chromium.org/2322004

Review URL: http://codereview.chromium.org/2367001

crawford/scripts,mjg59/scripts,nicescale/scripts,glevand/coreos--scripts,gtank/scripts,bcwaldon/coreos-scripts,zhang0137/scripts,nicescale/scripts,sigma/coreos-scripts,crawford/scripts,mischief/scripts,zhang0137/scripts,vmware/coreos-scripts,endocode/scripts,marineam/coreos-scripts,sigma/coreos-scripts,mjg59/scripts,andrejro/coreos--scripts,trnubo/scripts,endocode/scripts,BugRoger/scripts,fivethreeo/scripts,glevand/coreos--scripts,vmware/coreos-scripts,BugRoger/scripts,andrejro/coreos--scripts,BugRoger/scripts,mischief/scripts,vmware/coreos-scripts,mjg59/scripts,fivethreeo/scripts,coreos/scripts,crawford/scripts,fivethreeo/scripts,coreos/scripts,andrejro/coreos--scripts,bcwaldon/coreos-scripts,sigma/coreos-scripts,mischief/scripts,marineam/coreos-scripts,smilart/scripts,bcwaldon/coreos-scripts,trnubo/scripts,trnubo/scripts,gtank/scripts,endocode/scripts,zhang0137/scripts,gtank/scripts,smilart/scripts,smilart/scripts,nicescale/scripts,marineam/coreos-scripts