remove dependency on entrypoint
also rm glibc and swap .deb for .zip
from comments [here](https://github.com/ngrok/docker-ngrok/pull/1)
create a minimal, flexible entrypoint
per notes [here](https://www.notion.so/ngrok/docker-agent-spec-2076765fbd07499fa742f02b49e1f8a5)
* remove all of the env var stuff except cli args for config and authtoken
* change dockerfile `CMD`s to `ENTRYPOINT`s to allow arbitrary
subcommands and cli args to be used _with_ the environment variable
templating. With the previous design from the other repo, you had to
choose to use only cli arguments or only environment variables. Which is
why they had to support such a complicated mass of env vars. This way
seems far cleaner even if it removes the ability to run arbitrary
non-ngrok commands in the container.
review fixes
* `-config` -> `--config`
* mark entrypoint.sh executable beforehand and remove chmod calls
* save auth token to config file rather than cli args
* remove `set -x` to avoid logging auth tokens
* use a separate debian builder for debian image
cat authtoken into separate config file
make sure the agent uses authtoken config and default config if
`NGROK_AUTHTOKEN` is set but `NGROK_CONFIG` isn't
remove distroless
it's bigger than alpine so not worth supporting for now
move config files to `/var/lib/ngrok`
to avoid conflicting with potential user-mounted configs
add license
Zach Sherman