[Merge] lp:~jamesodhunt/upstart/bug-1324096 into lp:upstart

[Dimitri John Ledkov]

Asserts in test_control.c, since empty strings may not be added into a nih_str_array. Fix proposed here https://code.launchpad.net/~xnox/upstart/bug-1324096/+merge/222142
-- 
https://code.launchpad.net/~jamesodhunt/upstart/bug-1324096/+merge/221743
Your team Upstart Reviewers is requested to review the proposed merge of lp:~jamesodhunt/upstart/bug-1324096 into lp:upstart.