Moved SelectionResponder to fix build errors

.../sleuthkit/autopsy/corecomponents/SelectionResponder.java

.../org/sleuthkit/autopsy/datamodel/AbstractContentNode.java

Core/src/org/sleuthkit/autopsy/datamodel/Artifacts.java

Core/src/org/sleuthkit/autopsy/datamodel/HashsetHits.java

Core/src/org/sleuthkit/autopsy/datamodel/HostNode.java

Core/src/org/sleuthkit/autopsy/datamodel/KeywordHits.java

Core/src/org/sleuthkit/autopsy/datamodel/Tags.java

...hkit/autopsy/directorytree/DirectoryTreeTopComponent.java

Core/src/org/sleuthkit/autopsy/mainui/nodes/TreeNode.java

.../sleuthkit/autopsy/imagegallery/FileIDSelectionModel.java