A command-line tool for rotating the encryption key of a Firebase database that has been encrypted with [`firecrypt`](https://www.npmjs.com/package/firecrypt).  It can also remove the encryption altogether, or add it to an unencrypted database.

You should ensure that nobody accesses the database while the keys are being rotated.  Also be careful that any parts of your database not explicitly described in the `firecrypt` rules files but situated under an encrypted key are small enough to be read and written in a single chunk.

Options:

```
  -f, --firebase database   The unique id of the target realtime database (required).
  -a, --auth file           A JSON file with credentials for the database (required).
  -s, --spec file           The firecrypt rules JSON file (required).
  -o, --oldKey base64key    The old encryption key to be replaced.
  -n, --newKey base64key    The new encryption key to use.
  -c, --cpus number         the number of CPUs to use (defaults to all available).
  -h, --help                Display these usage instructions.
  -v, --verbose             Turn on verbose logging messages for debugging
```