Added option for disabling snackbar layout edge inset calculation

Sources/iOS/SnackbarController.swift

@@ -112,6 +112,13 @@ open class SnackbarController: TransitionController {
   }
 
   /**
+   A boolean that controls if layoutEdgeInsets of snackbar is adjusted
+   automatically.
+   */
+  @IBInspectable
+  open var automaticallyAdjustSnackbarLayoutEdgeInsets = true
+  
+  /**
    Animates to a SnackbarStatus.
    - Parameter status: A SnackbarStatus enum value.
    */
@@ -179,6 +186,8 @@ open class SnackbarController: TransitionController {
     snackbar.frame.origin.x = snackbarEdgeInsets.left
     snackbar.frame.size.width = view.bounds.width - snackbarEdgeInsets.left - snackbarEdgeInsets.right
     snackbar.frame.size.height = snackbar.heightPreset.rawValue
+    
+    if automaticallyAdjustSnackbarLayoutEdgeInsets {
       snackbar.layoutEdgeInsets = .zero
       if .bottom == snackbarAlignment {
         snackbar.frame.size.height += bottomLayoutGuide.length
@@ -191,6 +200,7 @@ open class SnackbarController: TransitionController {
       rootViewController.view.frame = view.bounds
       layoutSnackbar(status: snackbar.status)
     }
+  }
   
   open override func prepare() {
     super.prepare()