Clean up old-style 'T, args' uses of CreateInstanceOfType
Refactor and optimize JSIL.CreateInstanceOfType
Fix reflection invoke bugs introduced by fix for #484. Fixes issues #529 and #530.
Make generated call methods strict about parameter count.
Merge pull request #527 from iskiselev/AsyncBclProxies

Added BCL proxies for classes implemented in JSIL.Async.js
[Manual merge of PR #512 - kg]
  Fixes #381 and #508
  Adding support for Generic Closures.  Not the best implementation, but
  fixes the issues.  There might be a better more comprehensive
  implementation around closures at a later point.
Merge with master