Display visualizations already generated on landing page for viewable example

[ibnesayeed]

Add a block on the landing page to promote a few (3-5) of the most recent visualizations for users to have a quick look while still utilizing the cache.

[machawk1]

@ibnesayeed Can you clarify what you mean by "most recent visualizations"? An example would be helpful.

[ibnesayeed]

I mean the last few TimeMap visualizations that people have requested. When the server runs for the firs time, there will be nothing to serve, unless we always have something as the default. Then as more and more new requests arrive, the window of last few will keep moving.