QSqlTableModel::selectRow(): complete documentation

Mention in changes and document Qt version (merci à dfaure).
Follow-up to 291e2c7d54.

Change-Id: Ie5626e9cd268812c1173ca494ccd8d6bd9be2687
Reviewed-by: Honglei Zhang <honglei.zhang@nokia.com>

dist/changes-5.0.0

@@ -406,6 +406,9 @@ ignore the rest of the range.
 QSqlTableModel::indexInQuery() as example of how to implement in a
 subclass.
 
+* QSqlTableModel::selectRow(): This is a new method that refreshes a single
+row in the model from the database.
+
 * QSqlTableModel edit strategies OnFieldChange/OnRowChange QTBUG-2875
 Previously, after changes were submitted in these edit strategies, select()
 was called which removed and inserted all rows. This ruined navigation

src/sql/models/qsqltablemodel.cpp

@@ -392,6 +392,8 @@ bool QSqlTableModel::select()
 }
 
 /*!
+    \since 5.0
+
     Refreshes \a row in the model with values from the database table row matching
     on primary key values. Without a primary key, all column values must match. If
     no matching row is found, the model will show an empty row.