Drag & Drop and Swipe enhancements for DynamicListView

Several Drag  & Drop and Swipe enhancements when using the DynamicListView

1. Allow only a certain area within a list-item to be able to initiate a swipe or drag&drop
You can tell the adapters the resource-ID of the child-View of each list-item which should be used as the touch-target to initiate a swipe or drag&drop. When the user touches outside that child-View, swiping or dragging won't work.

2. When the user is busy swiping an item, don't allow it to change into a drag&drop.

3. Allow customizing the drag&drop hover-image.

(The commit 38b4364 "Fix build errors" can be ignored; it is just some changes to make it build on my system)