Merge pull request #25 from kalyansky/master

Fix error event in flow script
fix for ie10
Merge branch 'master' of https://github.com/apla/dataflo.ws into HEAD
Use falsy values for $empty
set $empty on completion of all task types
Merge pull request #26 from behrad/master

$empty now is set for all falsy values instead of just void values and all task types
fix self.failed being masked
Merge pull request #27 from behrad/master

failed tasks doesn't fail workflows
Update every.js

now every task can merge collected data into object
for require.js
workflow config for cb initiator now can be object
minor; prepare for test suite