Add db dump for contrib features

[bmartinez287]

The README has Syncing the Database from Production which is pretty important for any contributed features.

This feature could be one of those. #148
However, that does require some sample data. Even if is a truncated db.

[bmartinez287]

The db dumb could be in a folder on the repo like other projects have done such as the Florida Drupal camp that added it to support Drupalpod.

[geerlingguy]

Another option is using something like Default Content Deploy to have a default set of content for testing. I would rather keep the full database private as there are some things here or there which could be a security risk to leak, and sanitizing databases is difficult :(