Every time I restart dynamodb local and run "sls dynamodb start" the content of the DB is wiped

**Actual Behaviour**

i run `sls dynamodb start` - I populate the database, I stop dynamodb local and run it again, and table is recreated and content wiped.

This is my .yml configuration

```
dynamodb:
start:
migrate: true
inMemory: false
stages:
- ${self:provider.stage}

```
**Expected Behaviour**

Given that `inMemory:` is set to **false** I would expect the data to be written to disk and next time I restart the server the data should be there.

**Steps to reproduce it**

Just start server with `sls dynamodb start` - populate some data, and restart the server and data will be gone.

Reproduce the issue with the shown .yml configuration by running `sls dynamodb start`, populating a table, stopping the local server, and starting it again. Trace how the plugin handles persistence when `inMemory: false`; done means the table and its content remain after restart.

Written by the indexing model from the issue text.