taofed
make navbar responsive to changes in dimensions
[don't merge yet]
the issue i was having was that the navbar's right button wasn't adapting to screen resizes
this code mostly works (see edge case below), but it seems like it's going to be a pattern for many web components, as windows are much more flexible than on mobile. I wonder if we should factor out some of this code into a DimensionsAwareComponent and make other components that want to re-render on resize/orientation change extend from it. Internally in my own project, i'm using https://github.com/mvayngrib/react-native-orient for this kind of stuff
edge case: on the very first time I resize full screen to half-screen (I'm using the Spectacle App on OSX), the right button's css doesn't update, though the re-render does happen and with the correct style values. After that, it works fine, whether via Spectacle, or just dragging the edges.
