EditDialog: Improve handling of binary data in text mode

Make the EditDialog a bit more user friendly when editing binary data in
text mode:

Don't change back to the hex editor after changing any character.

Show the full binary data even if it contains a NULL byte.

Also (though a bit unrelated) disable rich text input for the text widget.

This partially fixes issue #19.

src/EditDialog.cpp

@@ -54,10 +54,15 @@ void EditDialog::loadText(const QByteArray& data, int row, int col)
     curCol = col;
     oldData = data;
 
-    ui->editorText->setPlainText(data);
+    QString textData = QString::fromUtf8(data.constData(), data.size());
+    ui->editorText->setPlainText(textData);
     ui->editorText->setFocus();
     ui->editorText->selectAll();
     hexEdit->setData(data);
+
+    // Assume it's binary data and only call checkDatyType afterwards. This means the correct input widget is selected here in all cases
+    // but once the user changed it to text input it will stay there.
+    ui->editorStack->setCurrentIndex(1);
     checkDataType();
 }
 
@@ -162,7 +167,6 @@ void EditDialog::checkDataType()
             ui->comboEditor->setVisible(false);
         } else {
             // It's not. So it's probably some random binary data.
-            ui->editorStack->setCurrentIndex(1);
 
             ui->labelType->setText(tr("Type of data currently in cell: Binary"));
             ui->labelSize->setText(tr("%n byte(s)", "", hexEdit->data().length()));

src/EditDialog.ui

@@ -93,6 +93,9 @@
       <property name="whatsThis">
        <string>This area displays information about the data present in this database cell</string>
       </property>
+      <property name="acceptRichText">
+       <bool>false</bool>
+      </property>
      </widget>
      <widget class="QWidget" name="editorBinary"/>
      <widget class="QScrollArea" name="editorImageScrollArea">