Terminolgy Change: "Playspace" -> "Room"

Valve's official terminology are "Room Setup" and "Tracking Universe". Changed our usage of "Playspace" to "Room" for clarity with the upcoming Room-Turn feature and existing Room-Drag feature when compared to nomenclature for other tools that exits out there.

Also slight clean up in readability of movecentertab's action functions.

src/res/qml/RootPage.qml

@@ -48,7 +48,7 @@ MyStackViewPage {
                    MyPushButton {
                        id: playSpaceButton
                        activationSoundEnabled: false
-                       text: "Play Space"
+                       text: "Room Settings"
                        Layout.fillWidth: true
                        onClicked: {
                            MyResources.playFocusChangedSound()
@@ -59,7 +59,7 @@ MyStackViewPage {
                    MyPushButton {
                        id: fixFloorButton
                        activationSoundEnabled: false
-                       text: "Playspace Fix"
+                       text: "Room Fix"
                        Layout.fillWidth: true
                        onClicked: {
                            MyResources.playFocusChangedSound()