feature request: splice (delete surroundings of form)

[jerielverissimo]

Hi, I start using this amazing plugin the only thing I'm missing from vim-sexp-mappings-for-regular-people is the dsf keybind that delete surroundings of form, I use this a lot with Clojure.
I don't know if this plugin already supports this feature, and if not how difficult it will be to implement this, looking on README I don't find this specific case.