add manifest reference to html

implement import/export, tweak styles, update readme, and add leaflet license

add web manifest, favicon; implement edit modal - just need import/export

implement menu that keeps track of overlays, sets home

detect location if home not set and offer to set home, add go-home button

add reset button to load from save data

fix button state on handler reset

add polygon support and use cancel/okCancel modals

use temporary file for srcmap instead of on-disk file

slim down build script slightly

fix modal and start planning polygon creation

cleanup a bit more after build

switch to central MapHandler instead of arrow functions everywhere

refine UI

add skeleton for most UI elements, implement cirlces

fix readme

add readme and license file

initial commit