Add DelayedTask.Delay for all targets except portable-net40 (fixes #30)
Add DelayedTask.WhenAll (fixes #31)
Add DelayedTask.WhenAny (fixes #32)
Update user guide with information about DelayedTask
Add unit tests for DelayedTask
Implement support for exception handling continuations (fixes #33)
Add description of `Catch` methods to the User Guide
Add unit tests for `Catch` methods
Merge pull request #37 from sharwell/delayed-task

Delayed task
Merge pull request #38 from sharwell/catch

Implement support for exception handling continuations