Allow the use to copy any text in a pass (#476)

The user may need to copy text from the pass for many reasons. For
example, to connect to the WiFi from Renfe trains company in Spain they
ask you for the train ticket number. Being able to just copy and paste
it into the form makes it much easier.

Co-authored-by: ligi <ligi@ligi.de>

android/src/main/res/layout/barcode.xml

@@ -55,5 +55,6 @@
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
             android:layout_gravity="center_horizontal"
-            android:paddingBottom="8dp" />
+            android:paddingBottom="8dp"
+            android:textIsSelectable="true" />
 </merge>

android/src/main/res/layout/pkpass_view_extra_data.xml

@@ -93,6 +93,7 @@
                 android:layout_width="match_parent"
                 android:layout_height="wrap_content"
                 android:fontFamily="sans-serif"
+				android:textIsSelectable="true"
                 android:padding="24dp"
                 android:visibility="gone"/>
     </LinearLayout>

android/src/main/res/layout/vertical_field_item.xml

@@ -12,6 +12,7 @@
         android:layout_height="wrap_content"
         android:gravity="center"
         android:fontFamily="sans-serif-light"
+        android:textIsSelectable="true"
         android:textSize="14sp"
         tools:text="Key"
         android:id="@+id/key" />
@@ -21,6 +22,7 @@
         android:layout_height="wrap_content"
 	android:gravity="center"
         android:fontFamily="sans-serif"
+        android:textIsSelectable="true"
         android:textSize="18sp"
         tools:text="Value"
         android:id="@+id/value" />