Revert encryption of secrets, blocks.

Existing data on s3 has to be encrypted before this is rolled out
so as to preserve data integrity and ensure accurate encryption status
is stored in the Block table.

Commits reverted -
a8f4be: "Check for None in migration 088."
c9bd77: "Helper script to re-encrypt secrets."
af6cb8: "New scheme for EAS passwords encryption."
eb47f4: "[SCHEMA][DEPENDENCIES] Encryption of secrets (passwords, refresh_tokens) and blocks."
        Conflicts:
	        inbox/models/roles.py
	        requirements.txt
	        tests/data/base_dump.sql
	        tests/general/test_storage.py

Migrations renamed, test DB updated too.

Sync runs as before.
All tests pass.