Do not start a task twice when runnning concurrent tasks
Do not start a task twice when runnning concurrent tasks

A started boolean was added to the task to indicate when a task has been
sterted. This is checked before a task is invoked.

cesarmarinhorj/jake,kedashoe/jake,kedashoe/jake,talves/jake,vinodpanicker/jake,vinodpanicker/jake,talves/jake,jakejs/jake,talves/jake,cesarmarinhorj/jake,cesarmarinhorj/jake,vinodpanicker/jake,jakejs/jake,kedashoe/jake