Wrapping expression to be awaited into Future.value

Not sure if using raw name in `make.identifier('Future.value’)` is OK.
Otherwise, trivial change.
Dotted Identifier

Fix as suggested by @kmillikin
Fixed test and pubspec
Restore pubspec
Merge pull request #65 from headinthebox/AwaitAnything

Await anything
Merge branch 'master' into await-for

Conflicts:
	lib/src/xform.dart