Add development flag

**Is your feature request related to a problem? Please describe.**
We want different island behavior when we are developing than in production.

## Tasks

- [ ] Add development flag to the island cmd parameters
- [ ] Don't run next server on develop (development server uses the same files as production, so it can't be ran at the same time). Until this point feature flag served as development flag for this case.
- [ ] Token should have a longer TTL on develop
- [ ] OTP should be hard-coded on develop