Closes #1530 by using `coin`
endpoint.

- PR increased the default gas prices to be like in testnet, making
transactions much more expensive for local development. It may break
tests for downstream dependencies.
- Removed helm chart since we use operator now. Is it okay @Voxelot
@rfuelsh?
- Fixed e2e binary to work with custom `base_asset_id`.
- Fixed e2e binary to work when wallet a and wallet b have many dust
coins by suing `coin` endpoint.
- Added json version of the `non_specific_tx` to simplify its support.

## Checklist
- [x] Breaking changes are clearly marked as such in the PR description
and changelog
- [x] New behavior is reflected in tests