apply staging html changes to others
add html-entities, as-str & escape-html helpers
major update dom ns: add create-dom! for hiccup style dom tree creation (but realising as actual dom nodes), update create! to support SVG, update set-attribs! to support :style, update add-class! to support multiple classes, add append! & create-text!
refactor/simplify all dom creation using new features in dom ns, remove need for hiccups dependency
minor style update for gallery info
update appengine version
remove laziness in various places
bugfix node rendering for v.slim scale & stretch nodes