Store documents from JSON data file to relaton-data-nist

[andrew2net]

The relaton-nist gem saves a JSON data file on local storage for searching use. In case using relaton as an API, it's run in an AWS Lambda container. Lambda has a read-only file system and doesn't allow saving files. relaton/relaton-calconnect#11.
We need to parse the data file and save the documents as separated files in the GitHub relaton-data-nist repository.

[ronaldtse]

Lambda has a read-only file system and doesn't allow saving files.

When we need to cache files in Lambda, we have to use an S3 bucket, I believe @phuonghuynh has already created it for you?