Would be nice to have a selection.selectChildren() (which could take for example 'g' for immediate node instead of all nested g, or empty for '*') shortcut for what might be very common - see https://stackoverflow.com/questions/20569670/d3-selector-for-immediate-children

Right now I had to research this and do this in Typescript (complains in Typescript even with latest @types/selection (so have to cast to any - yuck)

this.container.selectAll(function() {return this.children;} as any)

(where container is selection of my svg root).

see discussion in #63 as well.