Implement new when_all (working on #1278: Implement improved when_all/wait_all)
Fixing return value of when_all_n. This requires some additional thought, though.
Adjust docs and return type for when_all_n algning things with latest changes on master
Re-implementing wait_all using techniques similar to dataflow() and the new when_all. This fixes #1278: Implement improved when_all/wait_all
Merge branch 'master' into fixing_1278

Conflicts:
	hpx/lcos/when_all.hpp
Getting rid of an allocation in wait_all.
Adding an overload for when_all(vetor<shared_future<R>>) which slightly optimizes this case
Revert "Adding an overload for when_all(vetor<shared_future<R>>) which slightly optimizes this case"

This reverts commit 5af2a87ff5d075c9396a3c08cb6c93cf108472a1.
Merge pull request #1279 from STEllAR-GROUP/fixing_1278

Add improved when_all/wait_all