fix(art): Correct "Trash" icon, naming consistency

internal_packages/category-picker/lib/category-picker.cjsx

@@ -56,11 +56,11 @@ class CategoryPicker extends React.Component
     return <span></span> unless @_account
 
     if @_account?.usesLabels()
-      img = "ic-toolbar-tag.png"
+      img = "toolbar-tag.png"
       tooltip = "Apply Labels"
       placeholder = "Label as"
     else if @_account?.usesFolders()
-      img = "ic-toolbar-movetofolder.png"
+      img = "toolbar-movetofolder.png"
       tooltip = "Move to Folder"
       placeholder = "Move to folder"
     else

internal_packages/message-list/lib/thread-toggle-unread-button.cjsx

@@ -13,7 +13,7 @@ class ThreadToggleUnreadButton extends React.Component
             style={order: -105}
             title="Mark as #{fragment}"
             onClick={@_onClick}>
-      <RetinaImg name="icon-toolbar-markas#{fragment}@2x.png"
+      <RetinaImg name="toolbar-markas#{fragment}.png"
       mode={RetinaImg.Mode.ContentIsMask} />
     </button>
 

internal_packages/thread-list/lib/thread-buttons.cjsx

@@ -95,7 +95,7 @@ class ThreadBulkToggleUnreadButton extends React.Component
             className="btn btn-toolbar"
             title="Mark as #{fragment}"
             onClick={@_onClick}>
-      <RetinaImg name="icon-toolbar-markas#{fragment}@2x.png"
+      <RetinaImg name="toolbar-markas#{fragment}.png"
                  mode={RetinaImg.Mode.ContentIsMask} />
     </button>