[DSpace 7 Upgrade] Reimplement Community Tree Browser Aspect

[wwelling]

https://github.com/TAMULib/DSpace/blob/tamu-dspace-6.3/dspace/config/xmlui.xconf#L88

https://github.com/TAMULib/DSpace/blob/tamu-dspace-6.3/dspace/modules/xmlui/src/main/resources/aspects/CommunityTreeBrowser/sitemap.xmap

https://github.com/TAMULib/DSpace/blob/tamu-dspace-6.3/dspace/modules/xmlui/src/main/java/org/tdl/dspace/communityview/CommunityTreeBrowser.java

Add tamu theme shared component for collapsing sub communities and collections at the community collection views.

This shared component and community/collection views overridden to use it will require use of the shared component in theme-based overrides of the same community/collection views.

This component should include expand all and collapse all buttons.

To looks like

If possible, list children community/collection as tree and exclude the self community/collection as root of the tree.

Use component for collection and community browsing: https://labs.library.tamu.edu/dspace7/community-list

[jsavell]

Links to 6x implementation: https://github.com/TAMULib/DSpace/blob/tamu-dspace-6.3/dspace/modules/xmlui/src/main/java/org/tdl/dspace/communityview/CommunityTreeBrowser.java https://github.com/TAMULib/DSpace/blob/tamu-dspace-6.3/dspace/modules/xmlui/src/main/resources/aspects/CommunityTreeBrowser/sitemap.xmap https://github.com/TAMULib/DSpace/blob/tamu-dspace-6.3/dspace/modules/xmlui-mirage2/src/main/webapp/themes/Mirage2/scripts/community-list.js

[wwelling]

@jcreel has provided additional requirements for this issue to address the limitations of asynchronously expanding subcommunities and collections. He proposed that the expand all button only expand the current level of whichever has not been expanded. Collapse all should still collapse all expanded nodes.