It is tedious to test all the overloads of QString::append(),
so get the help of the compiler to do it. The framework
developed for this will be used in subsequent commits for
prepend and insert, too.
Change-Id: I89df581b6d037a5af80b34dd6b5d37ac7484c774
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>