Added tab navigation functional. (#721)

- Added tab navigation functional.
- In basic types added parentFlickable property, which will help to ensure, that the item is visible within flickable parent during tab navigation.
- Added focus state for some basic types.
- In PageType qml file added lastItemTabClicked function, which will help to focus tab bar buttons when the last tab on the current page clicked.
- Added Focus for back button for all pages and drawers.
- Added scroll on tab for Servers ListView on PageHome.

client/ui/qml/Pages2/PageSetupWizardTextKey.qml

@@ -14,6 +14,12 @@ PageType {
 
     defaultActiveFocusItem: textKey.textField
 
+
+    Item {
+        id: focusItem
+        KeyNavigation.tab: backButton
+    }
+
     FlickableType {
         id: fl
         anchors.top: parent.top
@@ -30,7 +36,9 @@ PageType {
             spacing: 16
 
             BackButtonType {
+                id: backButton
                 Layout.topMargin: 20
+                KeyNavigation.tab: textKey.textField
             }
 
             HeaderType {
@@ -75,6 +83,7 @@ PageType {
         anchors.bottomMargin: 32
 
         text: qsTr("Continue")
+        Keys.onTabPressed: lastItemTabClicked(focusItem)
 
         clickedFunc: function() {
             if (ImportController.extractConfigFromData(textKey.textFieldText)) {