With Class Template Argument Deduction users might want to use the constructor
itself instead of a separate helper function. In both cases it's possible to let
the compiler deduce the template arguments.
Try to make the usefulness of the helper function in the absence of CTAD still
clear in the documentation.
Change-Id: I9b07983c1fb276a6dd9e7ed4c3e606764e9b68ca
Reviewed-by: Ville Voutilainen <ville.voutilainen@qt.io>
4f077b7e5f