Fix our API, so that QStringList and QList<QString> are the
same thing.
This required a bit of refactoring in QList and moving the
indexOf(), lastIndexOf() and contains() method into
QListSpecialMethods. In addition, we need to ensure that
the QStringList(const QString&) constructor is still available
for compatibility with Qt 5.
Once those two are done, all methods in QStringList can be moved
into QListSpecialMethods<QString>.
Change-Id: Ib8afbf5b6d9df4d0d47051252233506f62335fa3
Reviewed-by: Andrei Golubev <andrei.golubev@qt.io>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>