Add task batcher to context.

Batch tasks to 100 tasks, as that is the limit of the taskqueue api.

Add tests for _task_batcher()
Update coverage to only check furious module
Fix stupid comment
Minor tweaks and tunes to the task batcher tests
Merge branch 'master' of wfgithub:WebFilings/furious into add_task_batcher

Conflicts:
	setup.cfg
Merge pull request #76 from WebFilings/add_task_batcher

Add task batcher