Hooked in feature packs to show in super search using tags in the FP manifests
Added some keywords to manifests for super search
[CL 2526727 by bruce nesbit in Main branch]
#nonjira
#branch UE4
Added ImagePadding to FSearchBoxStyle which allows custom padding around the various icons in the search box
Added Style to SuperSearchBox as TOptional (because it's in it's own module, it's easier to add "optional" args this way), and modified SearchBox to also use the same method, which means we reduce duplicate instances of the default search box style around the code.
[CL 2394951 by Andrew Brown in Main branch]
