searcher's search! behavior should use argument it's given

I tried passing an argument to the [:searcher.search command](https://github.com/LightTable/LightTable/blob/master/src/lt/objs/search.cljs#L244-L246) for [a plugin I'm working on](https://github.com/cldwalker/ltfiles/blob/8f6f90544d1ff047ed57a8a04d69d0548c2f9973/src/lt/plugins/ltfiles/developer.cljs#L57-L63). The search! behavior doesn't use what it's passed contrary the intent of the command. I left `->search-info` in the behavior for backwards compatibility.