PaginationTableViewWrapper: Add placeholder view for initial loading state

Sources/Structures/Views/AnyLoadingIndicator.swift

@@ -31,8 +31,8 @@ public struct AnyLoadingIndicator: Animatable {
     /// Initializer with indicator that should be wrapped.
     ///
     /// - Parameter _: indicator for wrapping.
-    public init<Indicator> (_ base: Indicator) where Indicator: LoadingIndicator {
-        self.internalView = base.view
+    public init<Indicator> (_ base: Indicator, backgroundView: UIView? = nil) where Indicator: LoadingIndicator {
+        self.internalView = backgroundView ?? base.view
         self.animatableView = base.view
     }