Added Docker environment setup

[nklyshko]

Replace for #123

[generalmimon]

To use layer caching more efficiently, the best practice is to first COPY "package.json" and "package-lock.json", then RUN npm install, and only then copy the rest of the files with COPY . .. See https://nodejs.org/en/docs/guides/nodejs-docker-webapp/ to see the pattern (don't forget to add .dockerignore) and https://docs.docker.com/get-started/09_image_best/#layer-caching for an explanation why this approach is better.

Also please use COPY instead of ADD, the reason is here: https://docs.docker.com/develop/develop-images/dockerfile_best-practices/#add-or-copy

[generalmimon]

Please use

Suggested change

	FROM node:17
	FROM node:16

instead. See https://nodejs.org/en/about/releases/ - odd-numbered (9, 11, etc.) releases become unsupported after 6 months and their use in production is discouraged.

[generalmimon]

Please use 127.0.0.1:8000 instead of localhost:8000.

The "automatic reload when a local change is detected" feature works only for the 127.0.0.1 hostname:

kaitai_struct_webide/src/autorefresh.ts

Lines 6 to 7 in a8f6f9c

	if(location.hostname === "127.0.0.1")
	checkModifications();

Also using localhost instead of 127.0.0.1 caused some 1 sec delay (but I have no idea what the cause was, and whether it still persists), see

kaitai_struct_webide/serve_files.py

Line 116 in fdc13bb

print "please use 127.0.0.1:%d on Windows (using localhost makes 1sec delay)" % PORT

(this is a different file for different purpose, unused by the current Web IDE version, but whatever)

---

Actually for the "automatic reload" to work and also for easier development, it would be nice if the Docker image didn't have to be manually rebuilt every time a change is made to the source files. This is certainly achievable with Docker using bind mounts, see https://docs.docker.com/get-started/06_bind_mounts/.

node serve.js --compile is already capable of watching file modifications and recompiling the app, so just creating the bind mount should be enough I guess.