Fixed updateCart and addToCart strings being swapped

Author: ajungg

build.gradle

@@ -24,7 +24,7 @@ allprojects {
     }
 
     project.ext {
-        sdkVersion='0.6.2'
+        sdkVersion='0.6.3'
         versionCode=1
 
         compileSdkVersion=27

ui/src/main/java/io/snabble/sdk/ui/scanner/ProductConfirmationDialog.java

@@ -243,9 +243,9 @@ public void onClick(View v) {
         });
 
         if (cartQuantity > 0) {
-            addToCart.setText(R.string.Snabble_Scanner_addToCart);
-        } else {
             addToCart.setText(R.string.Snabble_Scanner_updateCart);
+        } else {
+            addToCart.setText(R.string.Snabble_Scanner_addToCart);
         }
 
         close.setOnClickListener(new View.OnClickListener() {