added concurrency factor to benchmark
added njsproj files for examples and comparison
using memwatch to monitor heap usage
'comparison' improvements

- added 'fibonacci' function
- added metrics for heap use/GC
- exposed (but not explained) problem with asyncawait recursion
- noted recursion problem with 'co' example files
Set concurrency to useful default
Semaphore improves concurrency issue (WIP)
amended license
ref LICENSE in sln
Merge remote-tracking branch 'origin/concurrency' into develop
20-45% speedup

OLD:
2.2-2.4K samples/sec
105 full GCs

NEW:
2.9-3.2K samples/sec
36 full GCs
minor fix

as per
https://typescript.codeplex.com/wikipage?title=Writing%20Definition%20%28.d.ts%29%20Files
await optimisations (WIP)

no longer creates a new promise on each await
added example code and stub impl files
more stubbing
comments
WIP
basic working asynchronous iteration
Added exception safety, need better comments/docs
working fs tree walking example
reverted to old await()

newly optimised one breaks on largest() benchmark