mrhyde: aggressive hiding of member variables in clojure types

The clojure implementation doesn't seem to need visibility
of variables in maps, seqs, or their prototypes. So I am
now hiding most of those.

The effect should be that hyde-maps are now enumerable from
JavaScript via either Object.keys or (for k in m), because
the cljs cruft (and mrhyde cruft) is now effectively hidden -
except for the newly installed key/value pairs.
strokes: latest mrhyde goodness, don't need patch-args-map-to-obj

Now that mrhyde presents pristine maps, the patch-args-map-to-obj
method for multi-value maps is no longer necessary. And hopefully
things like transitions now work.
release: strokes-0.4.0
version bump to 0.4.1-SHAPSHOT

Also tweaked README.