Task Control and Worker Communication

Control task code execution and communication among workers during job and spmd block execution

Functions

`addAttachedFiles`	Attach files or folders to parallel pool
`spmdIndex`	Index of current worker in `spmd` block
`spmdSize`	Number of workers running current `spmd` block
`spmdCat`	Concatenate arrays on `spmd` workers
`spmdReduce`	Reduce arrays on `spmd` workers
`spmdPlus`	Add arrays from workers in `spmd` block
`spmdBarrier`	Synchronize workers in `spmd` block
`spmdBroadcast`	Send data to all workers in `spmd` block
`spmdProbe`	Determine whether data is available to current worker in `spmd` block
`spmdReceive`	Receive data from another worker in `spmd` block
`spmdSend`	Send data to another worker in `spmd` block
`spmdSendReceive`	Simultaneously send and receive data on worker in `spmd` block
`getCurrentJob`	Get job object from a worker running a job
`getCurrentCluster`	Get cluster object from a worker in a cluster
`getCurrentTask`	Task object currently being evaluated in this worker session
`getCurrentWorker`	Get worker object from current worker
`getAttachedFilesFolder`	Identify folder on a worker where attached files are copied to
`updateAttachedFiles`	Update attached files or folders on parallel pool

`parallel.Task`	Access task properties and behaviors
`parallel.Worker`	Access worker that ran task