Make default start method mount host files

[CyMule]

Previously docker compose up would use docker volumes. This pull request requires users to first make 2 folders, one for cache and one for unchained.

The override file now allows users to use docker volumes where it previously mounted the users 2 host files for the cache/unchained storage.

docker-compose.local.example is renamed to docker-compose.volume-override.yml because of the previosuly stated changes.

scripts/up.sh is deleted because the command docker compose up is now the primary command used instead of the longer override command.

Closes #379

[tjayrush]

This looks good. I made a few comments above.

Let's me try to summarize it, just so I understand.

Basically, you made the "Persist the files on the host machine's file system (i.e., ~/Data) the default." Give special instructions if you don't want the Unchained Index available externally.

You kind of flipped the sense of the install so that docker compose up is the version that persists outside the docker image.

Is that right?

[CyMule]

Your summary is correct!

I will take a look at the comments and make the appropriate changes. Thanks!

[tjayrush]

Thanks!