CFY-799 implement basic workflow tasks retry mechanism
CFY-799 implement basic interval between task retries
CFY-799 update docs
CFY-799 make task retries and retry interval configurable in task constructors
CFY-799 make -1 indicate infinite retries
CFY-799 refactor workflow task creation
CFY-799 use task retry configuration from bootstrap context
CFY-799 add retry information to task events
Merge branch 'develop' into feature/CFY-799-task-retries
CFY-799 improve task retry message
CFY-799 extend handler result api to allow retrying forever
CFY-799 update docs
CFY-799 maintain original workflow traceback on errors
CFY-799 restore error capture the way it was before a better way of doing this is come up with
Merge pull request #16 from cloudify-cosmo/feature/CFY-799-task-retries

Workflow task retries