Future should forward value as r-value
Add setResult member function to Delay
Add setResult member function to Promise
Merge pull request #88 from magicant/fix/future

Miscellaneous fixes in async module
Move TypeTag class to sesh::common

The TypeTag class should not be in the variant_impl namespace because
the type is directly used outside the namespace.
Remove unused function template in TokenParser
Avoid memory leak in a Future test case
Merge pull request #89 from magicant/fix/future

Avoid memory leak in a Future test case
Merge pull request #90 from magicant/refactor/typetag

 Move TypeTag class to sesh::common namespace
Change SystemClockTime and SteadyClockTime duration type

All API methods should return time in nanoseconds to reduce unnecessary
casts outside the Api class.
Add mutableSystemClockNow and mutableSteadyClockNow methods
Remove setSystemClockNow and setSteadyClockNow methods

in favor of the mutableSystemClockNow and mutableSteadyClockNow methods.
Add contains and find helper functions for containers
Add Trigger type alias and component types
Add Proactor abstract class
Add FileDescriptorSetFake test helper class
Add OpenFileDescriptionFake test helper class with empty implementation
Add OpenFileDescriptionCollection test helper class
Add PselectApiStub test helper class
WIP: Add Awaiter abstract class and its implementation