Enable Offline Access

I just came across a site developed by google: https://hoverboard-master.firebaseapp.com. It works offline once the site is loaded on both mobile and desktop. It's some technology called "Progressive Web Apps" which they're using https://github.com/gdg-x/hoverboard.

Offline access in NepalMap can be useful for people in Nepal since they don't have 24/7 access and internet isn't available everywhere. I've thought of some approaches to go about this:

## Option 1: Progressive Web App
- [ ] Research whether it's possible to implement it in a dynamic site like NepalMap.
- [ ] Looks for plugins in Django we can reuse.
- [ ] Test it with the existing architecture

## Option 2: Build a mobile app
- [ ] Wait for the development of chatbot. We'll have a JSON API.
- [ ] Use JSON API to build a hybrid mobile app using **React Native**(or some `other tech`)

## Option 3: Use option 1 and webview
- [ ] Add offline access to the site.
- [ ] Make a android app that fakes like it's native app. It'll hide all browser buttons and everything and loads the site
- Due to offline feature of site, it'll work without internet.