Change format of dist/changes-5.3.0 to what is used in changes-5.2.0

Change-Id: I9c11a126a70c25085f1465e2593bb878c736f8b4
Reviewed-by: Sergio Ahumada <sergio.ahumada@digia.com>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
QString: add missing contains(QLatin1String) overload

Since contains() just wraps indexOf(), which has a QLatin1String overload,
add one for contains(), too, for consistency.

[ChangeLog][QtCore][QString] Added QLatin1String overload of contains()

Change-Id: I2acc628a51e00789fb2b90400cf0c523a5b5e65a
Reviewed-by: Giuseppe D'Angelo <giuseppe.dangelo@kdab.com>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>