Fixes#58
I've tried adding a black space under the FAB, but that just reduces the
available vertical space while typing. This does reduce the usability
for small notes, as clicking on the FAB is much easier than clicking on
top-right back button or clicking the back button twice on Android.
* We no longer have a separate editing and browsing view - This does
mean we loose the ability to quick flip between notes by swiping.
However, this is more how a note editor would behave. I do later want to
add that capability back.
* We have 2 editors for now - Markdown and Raw. By default we use the
Markdown editor which can be toggled between Preview / Edit mode.
I later want to add a rich text editor and a todo editor as well.
