Re-use existing emulator if configured

[ayufan]

This makes the following changes:

• Re-uses existing emulator if configured.
• Destroy existing database before re-creating.

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[olavloite]

@ayufan What is the reason that you would like this change?

[olavloite]

Closing due to lack of response. Please feel free to reopen if this is something that you would like to pursue, but please include a description of why you would want this change.