Summary:
Add project_up script that auto-generates template files and runs skaffold commands via passing in prod/dev as the first argument.
Also adding gitignore and removing gitignore'd files that are now auto-created by the project_up script.

Test Plan:
```
# for Dev
make skaffold-dev
# for "Staging" (still the dev environment, just not watching changes)
make skaffold-staging
# for Prod (doesn't work because UI doesn't work in Docker as of this commit)
make skaffold-prod
```

Reviewers: kgandhi, michelle, zasgar

Reviewed By: zasgar

Differential Revision: https://phab.corp.pixielabs.ai/D91

GitOrigin-RevId: a10246ba4314a0f7c170cd9b70b85b1903719320