moved nav_back and nav_close images to CoreUI

MVMCoreUI/SupportingFiles/Media.xcassets/nav_back.imageset/Contents.json

@@ -2,17 +2,17 @@
   "images" : [
     {
       "idiom" : "universal",
-      "filename" : "back.png",
+      "filename" : "nav_back.png",
       "scale" : "1x"
     },
     {
       "idiom" : "universal",
-      "filename" : "back@2x.png",
+      "filename" : "nav_back@2x.png",
       "scale" : "2x"
     },
     {
       "idiom" : "universal",
-      "filename" : "back@3x.png",
+      "filename" : "nav_back@3x.png",
       "scale" : "3x"
     }
   ],

MVMCoreUI/SupportingFiles/Media.xcassets/nav_close.imageset/Contents.json

@@ -2,17 +2,17 @@
   "images" : [
     {
       "idiom" : "universal",
-      "filename" : "closeXBlack.png",
+      "filename" : "nav_close.png",
       "scale" : "1x"
     },
     {
       "idiom" : "universal",
-      "filename" : "closeXBlack@2x.png",
+      "filename" : "nav_close@2x.png",
       "scale" : "2x"
     },
     {
       "idiom" : "universal",
-      "filename" : "closeXBlack@3x.png",
+      "filename" : "nav_close@3x.png",
       "scale" : "3x"
     }
   ],

MVMCoreUI/Utility/MVMCoreUICommonViewsUtility+Extension.swift

@@ -13,7 +13,7 @@ public extension MVMCoreUICommonViewsUtility {
     /// Add the close button (x) to the top right of the view. TODO: update this logic.
     @objc static func addCloseButton(to view: UIView, action: @escaping ButtonAction, centeredVertically: Bool = false) -> Button {
         let button = Button()
-        if let image = MVMCoreUIUtility.imageNamed("closeXBlack")?.withRenderingMode(.alwaysTemplate) {
+        if let image = MVMCoreUIUtility.imageNamed("nav_close")?.withRenderingMode(.alwaysTemplate) {
             button.setImage(image, for: .normal)
         }
         button.tintColor = .black