Improvements to the usability of the number entry widgets (Priority, Level Emitter, Craft Amount): (#4737)

- Fixed tab order
- Introduced focus state for corner buttons
- Allowed the player to enter any text, but add validation that only persist it if it is a valid number
- Enter will now confirm these dialogs and return to the previous dialog
- The text field is automatically focused and its contents are selected

src/main/java/appeng/fluids/container/FluidConfigurableContainer.java

@@ -71,7 +71,7 @@ public abstract class FluidConfigurableContainer extends UpgradeableContainer im
 
     @Override
     protected void standardDetectAndSendChanges() {
-        if (Platform.isServer()) {
+        if (isServer()) {
             this.getSyncHelper().sendDiff(this.listeners);
 
             // clear out config items that are no longer valid (eg capacity upgrade removed)