New Container

Turn std.container into a package.

Delete container.d

Remove totalcontainer from package.
Create std.container.util.d and reference it from other containers.
Correct code coverage for containers.

Add containers for unit testing.

Make std.container.util public from any module.
Move around imports (avoid version(unittest)).

Remove irrelevant unittests.
Update to git head.
Merge totalcontainer.d with package.d
Merge remote-tracking branch 'origin/container_package'
Merge pull request #2174 from damianday/master

Turn std.container into a package.
Remove redundant @nogc attributes
Merge pull request #2270 from joakim-noah/nogc

Remove redundant @nogc attributes