Updated API calls, Accumulators API

• New forasync API
  • Has loop domains that express the iteration space for each dimension
  • Support strides
• Add support for accumulators to asyncs
• Asyncs data-structure are now runtime managed
• Define some macro for NULL parameters values

Forasync, Phasers

Add forasync and phasers support. Compatible OCR v0.8

Finish, Async, DDFs

Prototype release. Includes finish, async and ddfs constructs. Depends on OCR 0.7