Doc: Normalize \since usage

Although it's permitted to specify the project name together with
a version number for \since, it's unnecessary for Qt classes and
functions.

This change also normalizes the version formatting: '<major>.<minor>'

Change-Id: Ie5a43662077d13c31e241bcde8a7a2849d27d330
Reviewed-by: Leena Miettinen <riitta-leena.miettinen@qt.io>

src/corelib/global/qglobal.cpp

@@ -131,7 +131,7 @@ Q_STATIC_ASSERT_X(QT_POINTER_SIZE == sizeof(void *), "QT_POINTER_SIZE defined in
 
 /*!
     \fn QFlag::QFlag(uint value)
-    \since Qt 5.3
+    \since 5.3
 
     Constructs a QFlag object that stores the given \a value.
 */
@@ -145,7 +145,7 @@ Q_STATIC_ASSERT_X(QT_POINTER_SIZE == sizeof(void *), "QT_POINTER_SIZE defined in
 
 /*!
     \fn QFlag::QFlag(ushort value)
-    \since Qt 5.3
+    \since 5.3
 
     Constructs a QFlag object that stores the given \a value.
 */
@@ -158,7 +158,7 @@ Q_STATIC_ASSERT_X(QT_POINTER_SIZE == sizeof(void *), "QT_POINTER_SIZE defined in
 
 /*!
     \fn QFlag::operator uint() const
-    \since Qt 5.3
+    \since 5.3
 
     Returns the value stored by the QFlag object.
 */

src/corelib/tools/qstring.cpp

@@ -10107,7 +10107,7 @@ bool QStringRef::endsWith(const QStringRef &str, Qt::CaseSensitivity cs) const
 */
 
 /*! \fn bool QStringRef::contains(QLatin1String str, Qt::CaseSensitivity cs) const
-    \since 4,8
+    \since 4.8
     \overload contains()
 
     Returns \c true if this string reference contains an occurrence of

src/corelib/tools/qstringlist.cpp

@@ -716,7 +716,7 @@ int QtPrivate::QStringList_lastIndexOf(const QStringList *that, const QRegularEx
 /*!
     \fn int QStringList::removeDuplicates()
 
-    \since  4.5
+    \since 4.5
 
     This function removes duplicate entries from a list.
     The entries do not have to be sorted. They will retain their

src/network/socket/qnativesocketengine.cpp

@@ -761,7 +761,9 @@ bool QNativeSocketEngine::leaveMulticastGroup(const QHostAddress &groupAddress,
     return d->nativeLeaveMulticastGroup(groupAddress, iface);
 }
 
-/*! \since 4.8 */
+/*!
+    \since 4.8
+*/
 QNetworkInterface QNativeSocketEngine::multicastInterface() const
 {
     Q_D(const QNativeSocketEngine);
@@ -770,7 +772,9 @@ QNetworkInterface QNativeSocketEngine::multicastInterface() const
     return d->nativeMulticastInterface();
 }
 
-/*! \since 4.8 */
+/*!
+    \since 4.8
+*/
 bool QNativeSocketEngine::setMulticastInterface(const QNetworkInterface &iface)
 {
     Q_D(QNativeSocketEngine);

src/widgets/graphicsview/qgraphicsitem.cpp

@@ -6596,7 +6596,7 @@ QGraphicsItem *QGraphicsItem::commonAncestorItem(const QGraphicsItem *other) con
 }
 
 /*!
-    \since 4,4
+    \since 4.4
     Returns \c true if this item is currently under the mouse cursor in one of
     the views; otherwise, false is returned.
 

src/widgets/widgets/qmainwindow.cpp

@@ -676,7 +676,7 @@ void QMainWindow::setCentralWidget(QWidget *widget)
 
     The ownership of the removed widget is passed to the caller.
 
-    \since Qt 5.2
+    \since 5.2
 */
 QWidget *QMainWindow::takeCentralWidget()
 {

src/widgets/widgets/qtabbar.cpp

@@ -1448,7 +1448,7 @@ static QString computeElidedText(Qt::TextElideMode mode, const QString &text)
 
 /*!
     Returns the minimum tab size hint for the tab at position \a index.
-    \since Qt 5.0
+    \since 5.0
 */
 
 QSize QTabBar::minimumTabSizeHint(int index) const