Print failure message if provided

[vizio360]

I've noticed that the failure message contained in the result items wasn't printed out on the console. Only the trace | trace.stack was. This pull request prints the message as well if provided.

[vizio360]

Ok just noticed a side effect.
My fix was specifically for jasmine waitsFor timeout failures, it didn't print out the time out message provided to waitsFor, but now it prints the message twice for all the other failures (the message is included in the trace.stack property)

need to look into it again, but I'll keep this pull request open so people can have a look and maybe come back with a solution before me

[vizio360]

found a simpler solution. If trace.stack is not defined just print the message instead of the trace object which will just be printed out as [Object Object].